ASTM F3502-24

Standard Specification for Barrier Face Coverings

SCOPE
1.1 This specification is intended to help ensure barrier face coverings meeting the stated requirements provide (1) a means of source control for individual wearers by reducing expelled aerosols from the wearer’s nose and mouth into the air; and (2) a degree of particulate filtration that potentially reduces the amount of aerosols inhaled by the wearer.
Note 1: The source control/protection provided by barrier face coverings depends on several factors not considered in this specification, such as material degradation from wearer challenges including perspiration, talking, sneezing, and the length of time the barrier face covering is worn. Further research is needed to expand the evidence base for the protective effect of face coverings and, in particular, to identify the combinations of materials that maximize both their blocking and filtering effectiveness, as well as fit, comfort, durability, and consumer appeal. (https://www.cdc.gov/coronavirus/2019-ncov/more/masking-science-sars-cov2.html.)
Note 2: There are currently no established methods for measuring outward leakage from a barrier face covering, medical mask, or respirator. Nothing in this specification addresses or implies a quantitative assessment of outward leakage and no claims can be made about the degree to which a barrier face covering reduces expired human-generated aerosols.  
1.2 This specification establishes minimum design, performance (testing), labeling, user instruction, reporting and classification, and conformity assessment requirements for barrier face coverings.  
1.2.1 Design criteria include setting minimum areas of face coverage over the wearer’s nose and mouth, prohibiting open vents or valves, requiring a means for retaining the barrier face covering on the wearer’s head, and providing a representation of product sizing. Manufacturers are further required to perform a design analysis for assessing leakage of exhaled air from the barrier face covering where the general approach is described in the product report. Manufacturers are permitted to conduct quantitative testing as specified in this specification to supplement the design analysis. Accessories, such as braces or other devices that allow the barrier face covering to better conform to the wearer’s face, are addressed as part of this specification if used for the purpose of reducing leakage.  
1.2.2 Performance and testing criteria define minimum barrier face covering filtration efficiency and airflow resistance performance properties. Sub-micron particulate filtration efficiency represents the ability to capture and reduce respirable aerosols that potentially contain viruses and bacteria. Airflow resistance represents the wearer’s ease of breathing or breathability while wearing the barrier face covering. The impact of repeated cleaning or laundering on continued performance is applied for measuring performance properties for those barrier face coverings that are intended for reuse. Manufacturers are permitted to also provide test results for bacterial filtration efficiency (BFE) as supplemental information to the mandatory performance measurement of sub-micron particulate filtration efficiency.
Note 3: The principal performance criteria for barrier face covering determined by testing are sub-micron particle filtration efficiency and airflow resistance. Quantitative leakage assessment testing is optional for information purposes and is not required. This testing is not likely to be representative of outward leakage from the barrier face covering and should not be claimed to represent the amount of source control offered by the face covering. Bacterial filtration efficiency testing is also optional and not required. It is significantly different than sub-micron filtration efficiency, and the results of BFE testing cannot be interchanged or directly compared.  
1.2.3 Labeling requirements specify the minimum content for labels that appear on the barrier face cover...

General Information

• Status: Published
• Publication Date: 31-Jan-2024
• ICS: 13.340.30 - Respiratory protective devices
• Technical Committee: F23 - Personal Protective Clothing and Equipment
• Drafting Committee: F23.65 - Respiratory

Relations

• Replaces: ASTM F3502-23a - Standard Specification for Barrier Face Coverings
• Effective Date: 01-Feb-2024
• Referred By: ASTM F2100-23 - Standard Specification for Performance of Materials Used in Medical Face Masks
• Effective Date: 01-Feb-2024

Overview

ASTM F3502-24: Standard Specification for Barrier Face Coverings outlines requirements for the design, performance, testing, labeling, and conformity assessment of barrier face coverings. These coverings are intended to provide source control by reducing the expulsion of aerosols from the wearer and offering a degree of particulate filtration to potentially reduce inhaled aerosols. Developed by ASTM International, this standard sets a nationally recognized foundation for assessing non-medical face coverings used in public and workplace settings.

This specification was created in response to the global COVID-19 pandemic to address a need for standardized performance criteria for face coverings that are neither medical masks nor respirators but still play a role in reducing disease transmission and inhalation of particulate matter.

Key Topics

• Scope and Objective: ASTM F3502-24 applies to both disposable and reusable barrier face coverings designed to cover at least the wearer’s nose and mouth. The standard does not cover medical masks (ASTM F2100) or approved respirators (42 CFR Part 84).
• Design and Fit: Face coverings must meet minimum requirements for facial coverage, fit snugly to reduce gaps, and avoid features such as vents or valves that could compromise source control. Retention systems (like ear loops or headbands) must keep the covering in place during normal use.
• Performance Criteria:
  • Sub-micron Particulate Filtration Efficiency – Face coverings must meet minimum filtration efficiency, indicated as the percentage of sub-micron particles blocked by the material.
  • Airflow Resistance (Breathability) – The standard establishes a maximum airflow resistance to ensure wearer comfort and breathability.
  • Durability and Reuse – For reusable products, effectiveness must be maintained through the specified maximum number of laundering or cleaning cycles.
• Labeling and Documentation: Clear labeling regarding compliance, intended use, care instructions, and limitations is mandatory. Suppliers must provide a Declaration of Conformity to affirm that all requirements have been met.
• Safety Considerations: Materials must be non-irritating, non-toxic, and comply with applicable flammability regulations. The standard excludes claims related to antimicrobial properties or medical efficacy.

Applications

• Public Health Use: Barrier face coverings are recommended for the general population in settings where source control and reduced inhalation of aerosols are needed, such as public transportation, retail, workplaces, and educational institutions.
• Comparative Assessment: By setting standardized minimum requirements, ASTM F3502-24 enables manufacturers, distributors, and consumers to objectively compare the effectiveness and usability of different face covering products.
• Reusable and Disposable Options: The standard covers both single-use and reusable face coverings, accommodating a range of consumer needs and supporting environmental considerations.
• Workplace Safety Programs: Employers can reference ASTM F3502-24 to select barrier face coverings that meet recognized safety and comfort standards for non-medical applications.

Related Standards

When evaluating or specifying barrier face coverings, the following standards are relevant:

• ASTM F2100 – Specification for Performance of Materials Used in Medical Face Masks
• ASTM F3407 – Test Method for Respirator Fit Capability for Negative-Pressure Half-Facepiece Respirators
• ASTM F3050 – Guide for Conformity Assessment of Personal Protective Clothing and Equipment
• 16 CFR Part 1610 – Flammability of Clothing Textiles
• ISO/IEC 17025 – General Requirements for the Competence of Testing and Calibration Laboratories
• NIOSH/CDC TEB-APR-STP-0059 – Determination of Particulate Filter Efficiency

By following the requirements set forth in ASTM F3502-24, manufacturers can provide barrier face coverings that are effective, safe, and reliable for source control and filtration, thus supporting public health and workplace safety initiatives.

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: F3502 − 24
Standard Specification for
Barrier Face Coverings
This standard is issued under the fixed designation F3502; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
INTRODUCTION
This is the first ASTM standard to address this type of product. The standard was primarily
established in response to the global COVID-19 pandemic beginning in 2019 to address a product that
is neither a medical face mask per ASTM Specification F2100 for providing source control, nor a
respirator for providing inhalation protection as defined by regulatory requirements specified in the
United States under 42 CFR Part 84.
This specification is intended to establish a national standard baseline for a source control device.
This standard brings value by specifying minimum design, performance, and testing requirements and
allowing comparison of products by end users where current guidelines have been limited. Evolving
literature suggests that barrier face coverings could reduce the potential for disease transmission, as
well as offering a reduction of inhalation particulate matter by the wearer. The focus of this
specification is to identify how the device should perform in terms of source control/protection,
comfort, and reuse potential. The level of source control/protection depends on how well particles are
blocked from going through the barrier face covering and minimizing the amount of leakage that may
occur around the perimeter of the barrier face covering. The specific performance property for
filtration efficiency provides a greater challenge than most other particulate filtration tests, including
BFE, based on the use of smaller particles and more rigorous test conditions. Barrier face coverings
must be comfortable enough for individuals to be willing to wear them for long periods of time.
Requirements for breathing resistance were incorporated into the specification. The final performance
criterion was the potential for reuse of the barrier face covering, so the possibility of reuse was
identified in the specification.
Users of this standard are directed to Section 1 (Scope) and Section 4 (Significance and Use) to
understand the specific areas addressed by this standard and its limitations, along with the reasons for
choice of specific requirements. Users of this standard are further directed to the specific caveats for
this standard that are included in 1.3 – 1.11. The subcommittee responsible for this standard intends
to further evolve this specification for addressing new knowledge about disease transmission reduction
and barrier face covering design, performance, labeling, conformity assessment, and other aspects of
these products’ safety, health, and environmental impact as this information becomes available.
1. Scope a degree of particulate filtration that potentially reduces the
amount of aerosols inhaled by the wearer.
1.1 This specification is intended to help ensure barrier face
coverings meeting the stated requirements provide (1) a means
NOTE 1—The source control/protection provided by barrier face cov-
erings depends on several factors not considered in this specification, such
of source control for individual wearers by reducing expelled
as material degradation from wearer challenges including perspiration,
aerosols from the wearer’s nose and mouth into the air; and (2)
talking, sneezing, and the length of time the barrier face covering is worn.
Further research is needed to expand the evidence base for the protective
effect of face coverings and, in particular, to identify the combinations of
1 materials that maximize both their blocking and filtering effectiveness, as
This specification is under the jurisdiction of ASTM Committee F23 on
well as fit, comfort, durability, and consumer appeal. (https://
Personal Protective Clothing and Equipment and is the direct responsibility of
www.cdc.gov/coronavirus/2019-ncov/more/masking-science-sars-
Subcommittee F23.65 on Respiratory.
cov2.html.)
Current edition approved Feb. 1, 2024. Published March 2024. Originally
NOTE 2—There are currently no established methods for measuring
approved in 2021. Last previous edition approved in 2023 as F3502 – 23a. DOI:
10.1520/F3502-24. outward leakage from a barrier face covering, medical mask, or respirator.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
F3502 − 24
Nothing in this specification addresses or implies a quantitative assess-
sub-micron particulate filtration efficiency and airflow resis-
ment of outward leakage and no claims can be made about the degree to
tance tests have been performed by a laboratory accredited for
which a barrier face covering reduces expired human-generated aerosols.
conducting these tests.
1.2 This specification establishes minimum design, perfor-
NOTE 4—This specification does not provide for any form of
mance (testing), labeling, user instruction, reporting and
provisional, limited, or partial conformance of barrier face coverings since
classification, and conformity assessment requirements for
their compliance with this specification is a function of meeting all
barrier face coverings. performance requirements, including specific filtration efficiency and
breathability requirements, as well as all applicable design, labeling,
1.2.1 Design criteria include setting minimum areas of face
reporting, and user information requirements.
coverage over the wearer’s nose and mouth, prohibiting open
vents or valves, requiring a means for retaining the barrier face 1.3 This specification addresses barrier face coverings that
are either disposable or reusable.
covering on the wearer’s head, and providing a representation
of product sizing. Manufacturers are further required to per-
1.4 This specification does not address the unique additional
form a design analysis for assessing leakage of exhaled air
performance attributes of barrier face coverings that exist for
from the barrier face covering where the general approach is
certain applications, such as flame-resistant apparel used in
described in the product report. Manufacturers are permitted to
environments where there are flame, high heat, electrical arc,
conduct quantitative testing as specified in this specification to
or related hazards, but does recommend that barrier face
supplement the design analysis. Accessories, such as braces or
coverings also conform to other standards as applicable.
other devices that allow the barrier face covering to better
1.5 This specification does not address the use of antimi-
conform to the wearer’s face, are addressed as part of this
crobial or antiviral materials, finishes, or mechanisms, nor the
specification if used for the purpose of reducing leakage.
use of drugs, biologics, or nanoparticles in barrier face cover-
1.2.2 Performance and testing criteria define minimum bar-
ings. This specification also does not address the efficacy of
rier face covering filtration efficiency and airflow resistance
cleaning agents or other chemicals for cleaning, disinfecting, or
performance properties. Sub-micron particulate filtration effi-
sanitizing barrier face coverings.
ciency represents the ability to capture and reduce respirable
aerosols that potentially contain viruses and bacteria. Airflow
NOTE 5—Claims made about the use of antimicrobial materials,
resistance represents the wearer’s ease of breathing or breath-
finishes, or mechanisms; or the use of drugs, biologics, or nanoparticles in
any product subject the manufacturer to regulatory oversight by govern-
ability while wearing the barrier face covering. The impact of
ment agencies, including the U.S. Food and Drug Administration in the
repeated cleaning or laundering on continued performance is
United States, which applies additional safety and efficacy requirements to
applied for measuring performance properties for those barrier
these products. See 5.1.2 for the requirement of nontoxic and non-
face coverings that are intended for reuse. Manufacturers are
irritating materials used in the construction of barrier face coverings.
permitted to also provide test results for bacterial filtration
1.6 This specification does not address requirements for
efficiency (BFE) as supplemental information to the mandatory
medical face masks, which are covered in Specification F2100.
performance measurement of sub-micron particulate filtration
1.7 Nothing in this specification is intended to contradict or
efficiency.
replace criteria that are established in 42 CFR Part 84 for
NOTE 3—The principal performance criteria for barrier face covering
air-purifying respirators or requirements for use of respirators
determined by testing are sub-micron particle filtration efficiency and
in accordance with 29 CFR 1910.134.
airflow resistance. Quantitative leakage assessment testing is optional for
information purposes and is not required. This testing is not likely to be
1.8 Nothing in this specification is intended to imply that
representative of outward leakage from the barrier face covering and
barrier face coverings qualify as approved respiratory protec-
should not be claimed to represent the amount of source control offered by
tion devices or have FDA clearance for use in a healthcare
the face covering. Bacterial filtration efficiency testing is also optional and
not required. It is significantly different than sub-micron filtration setting.
efficiency, and the results of BFE testing cannot be interchanged or
1.9 Nothing in this specification is intended to imply that
directly compared.
barrier face coverings should be placed on very young children
1.2.3 Labeling requirements specify the minimum content
(<2 years), anyone who has trouble breathing, or anyone who
for labels that appear on the barrier face covering, its imme-
is unconscious, incapacitated, or otherwise unable to remove
diate packaging, and if different, point-of-sale packaging.
barrier face coverings without assistance.
1.2.4 User instructions are required to guide selection and
1.10 The values stated in SI units or in other units shall be
sizing, proper use (positioning and adjustment), and care
regarded separately as standard. The values stated in each
including cleaning or laundering if product reuse is intended;
system must be used independently of the other, without
inform on product cautions and limitations; and describe
combining values in any way.
product replacement and disposal procedures.
NOTE 6—There are several aspects that relate to the material composi-
1.2.5 Conformity assessment is demonstrated with a Sup-
tion and design of barrier face coverings that are not addressed in this
plier Declaration of Conformity (SDOC) following Guide
specification but warrant attention relative to their safety, health effects,
F3050, Annex A3, Model A. The SDOC states that each barrier
and impact on the environment, including but not limited to: leaching of
potentially toxic finishes, inhalable toxic substances from materials, and
face covering labeled as compliant has met all of the require-
bioburden inhibitors subject to regulatory oversight.
ments of this specification including design criteria, perfor-
mance criteria, test methods, labeling, and user information. 1.11 This standard does not purport to address all of the
Additionally, conformance to this specification requires that safety concerns, if any, associated with its use. It is the
F3502 − 24
responsibility of the user of this standard to establish appro- ISO 16900-5 Respiratory Protective Devices—Methods of
priate safety, health, and environmental practices and deter- Test and Test Equipment—Part 5: Breathing Machine,
mine the applicability of regulatory limitations prior to use. Metabolic Simulator, RPD Headforms and Torso, Tools
1.12 This international standard was developed in accor- and Verification Tools
dance with internationally recognized principles on standard- ISO/IEC 17025 General Requirements for the Competence
ization established in the Decision on Principles for the of Testing and Calibration Laboratories
Development of International Standards, Guides and Recom-
2.5 Federal Regulations:
mendations issued by the World Trade Organization Technical
16 CFR Part 1610 Standard for the Flammability of Clothing
Barriers to Trade (TBT) Committee.
Textiles
16 CFR Part 303 Rules and Regulations Under the Textile
2. Referenced Documents
Fiber Products Identification Act
16 CFR Part 423 Care Labeling of Textile Wearing Apparel
2.1 ASTM Standards:
and Certain Piece Goods as Amended
D3938 Guide for Determining or Confirming Care Instruc-
29 CFR 1910.134 Respiratory Protection
tions for Apparel and Other Textile Products
42 CFR Part 84 Approval of Respiratory Protective Devices
D5489 Guide for Care Symbols for Care Instructions on
Textile Products 2.6 NPPTL Standard Test Procedure:
F1494 Terminology Relating to Protective Clothing TEB-APR-STP-0059 Determination of Particulate Filter Ef-
F1506 Performance Specification for Flame Resistant and
ficiency Level for N95 Series Filters Against Solid Par-
Electric Arc Rated Protective Clothing Worn by Workers ticulates for Non-Powered, Air-Purifying Respirators
Exposed to Flames and Electric Arcs
2.7 NFPA Standard:
F2100 Specification for Performance of Materials Used in
NFPA 2112 Standard on Flame-Resistant Clothing for Pro-
Medical Face Masks
tection of Industrial Personnel Against Short-Duration
F2101 Test Method for Evaluating the Bacterial Filtration
Thermal Exposures from Fire
Efficiency (BFE) of Medical Face Mask Materials, Using
a Biological Aerosol of Staphylococcus aureus 3. Terminology
F2302 Performance Specification for Labeling Protective
3.1 Definitions:
Clothing Which Provides Resistance to Incidental Expo-
3.1.1 aerosol, n—a suspension of solid or liquid particulate
sures to Heat or Open Flame
matter in a gas.
F3050 Guide for Conformity Assessment of Personal Pro-
3.1.2 airflow resistance, n—in the testing of a barrier face
tective Clothing and Equipment
covering, the measured pressure drop across the barrier face
F3407 Test Method for Respirator Fit Capability for
covering under specified test conditions.
Negative-Pressure Half-Facepiece Particulate Respirators
3.1.2.1 Discussion—This specification involves measuring
2.2 AATCC Monograph:
airflow resistance of the barrier face covering during initial
M14 Guidance and Considerations for General Purpose
portion of sub-micron particulate filtration efficiency test for
Textile Face Coverings: Adult
which specific sample mounting and airflow conditions are set.
2.3 ANSI/ASQC Standard:
3.1.3 bacterial filtration effıciency (BFE), n—the effective-
ANSI/ASQC Z1.4 Sampling Procedures and Tables for In-
ness of a material in preventing the passage of aerosolized
spection by Attributes
bacteria, expressed as the percentage of a known quantity that
2.4 ISO Standards:
does not pass through the barrier face covering at a given
ISO 2859-1 Sampling Procedures for Inspection by
aerosol flow rate.
Attributes—Part 1: Sampling Schemes Indexed by Accep-
3.1.3.1 Discussion—In this specification, BFE is only an
tance Quality Limit (AQL) for Lot-by-Lot Inspection
optional reported test and not part of the requirements. BFE
ISO/ANSI/AAMI 10993-5 Biological Evaluation of Medical
testing primarily involves the evaluation of larger sized par-
Devices—Part 5: Tests for In Vitro Cytotoxicity
ticles and lower exposure conditions as compared to sub-
ISO/ANSI/AAMI 10993-10 Biological Evaluation of Medi-
micron particulate filtration efficiency.
cal Devices—Part 10: Tests for Irritation and Skin Sensi-
3.1.4 barrier face covering, n—a product worn on the face,
tization
specifically covering at least the wearer’s nose and mouth, with
the primary purpose of providing source control and to provide
a degree of particulate filtration to reduce the amount of
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
inhaled aerosols.
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website.
3 6
Available from American Association of Textile Chemists and Colorists Available from U.S. Government Printing Office, Superintendent of
(AATCC), P.O. Box 12215, Research Triangle Park, NC 27709-2215, http:// Documents, 732 N. Capitol St., NW, Washington, DC 20401-0001, http://
www.aatcc.org. www.access.gpo.gov.
4 7
Available from American Society for Quality (ASQ), 600 N. Plankinton Ave., Available from National Personal Protective Technology Laboratory (NPPTL),
Milwaukee, WI 53203, http://www.asq.org. https://www.cdc.gov/niosh/npptl/stps/pdfs/TEB-APR-STP-0059-508.pdf.
5 8
Available from American National Standards Institute (ANSI), 25 W. 43rd St., Available from National Fire Protection Association (NFPA), 1 Batterymarch
4th Floor, New York, NY 10036, http://www.ansi.org. Park, Quincy, MA 02169-7471, http://www.nfpa.org.
F3502 − 24
3.1.4.1 Discussion—In this specification, barrier face cov- 3.1.9 medical face mask, n—an item of protective clothing
erings are assessed for airflow resistance; filtration perfor- designed to protect portions of the wearer’s face, including the
mance using sub-micron particulate filtration efficiency testing; mucous membrane areas of the wearer’s nose and mouth, from
and the degree of face coverage per a leakage assessment using contact with blood and other body fluids during medical
procedures.
a product design analysis that can be supplemented by quan-
titative testing using test subjects. 3.1.9.1 Discussion—Medical face masks include surgical
masks, procedure masks, isolation masks, laser masks, dental
3.1.5 conformity assessment, n—demonstration that speci-
masks, and patient care masks. Isolation masks, laser masks,
fied requirements relating to a product, process, system,
dental masks, and patient care masks are considered isolation
person, or body have been fulfilled. F3050
masks. For many user groups, the term “mask” has become
3.1.6 design analysis, n—a process intended to verify that
synonymous with any product worn on the wearer’s face that
the barrier face covering provides coverage of at least the
offers a level of filtration efficiency; however, in the context of
wearer’s nose and mouth and to identify potential leakage
this specification, “mask” refers only to medical face masks
pathways in the design of a barrier face covering as worn by an
that are different from barrier face coverings. Requirements for
intended population.
medical face masks are provided in Specification F2100. This
specification is not intended to address regulatory require-
3.1.6.1 Discussion—In this specification, a design analysis
ments.
is used by the manufacturer for assessing the coverage pro-
vided and leakage associated with a barrier face covering when
3.1.10 respirator, n—personal protective equipment (PPE)
worn by the intended user population. A design analysis does
designed to protect the wearer from inhalation of hazardous
not provide quantitative measurements of leakage around the
contaminants.
perimeter of the barrier face covering.
3.1.10.1 Discussion—Barrier face coverings are not de-
signed to meet the performance requirements of NIOSH-
3.1.7 flammability, n—a quality of a product related to its
approved respirators. For the purpose of this specification,
rate of flame spread when contacted by a flame source.
healthcare workers are typically instructed to wear filtering
3.1.7.1 Discussion—In this specification, flammability ap-
facepiece respirators with N95 or higher levels of filtration
plies to barrier face coverings as determined by 16 CFR Part
efficiency as defined in 42 CFR Part 84 that are intended to
1610 as part of the Consumer Product Safety Commission
protect the wearer from exposure to pathogenic biological
regulations for wearing apparel. However, products that com-
aerosols. See also the definition for surgical N95 respirators.
ply with these regulations by having Class 1 or 2 flammability
3.1.11 reusable, adj—referring to the ability of a product to
are considered not flame resistant when exposed to flame, high
be used and laundered or cleaned multiple times and maintain
heat, electrical arc, or other thermal hazards.
its specified performance characteristics.
3.1.8 leakage assessment, n—the evaluation of a barrier face
3.1.11.1 Discussion—The use of the term “reusable” in this
covering for its potential to fit the wearer’s face by at least
specification is intended to distinguish types of barrier face
covering their nose and mouth and to reduce the likelihood of
coverings that are durable and that can be further subjected to
leakage of unfiltered air between the wearer and the outside
laundering or cleaning which permits their use multiple times
environment.
until they are damaged, cannot be effectively cleaned, or have
3.1.8.1 Discussion—In this specification, the leakage as-
surpassed the expiration date or are beyond the manufacturer’s
sessment addresses the potential for aerosol passing around the
designated service life.
perimeter of the barrier face covering and applies to both
3.1.12 service life, n—in the specification of barrier face
inward and outward leakage. When quantitative testing is
coverings, the maximum number of use and laundering or
performed according to 8.3, the leakage assessment will also
cleaning cycles that barrier face coverings can undergo and still
include the measurement of any aerosol that passes through the
maintain their performance properties.
barrier face covering. This quantitative testing measures in-
3.1.12.1 Discussion—For the purpose of this specification,
ward leakage that is presented as the ratio of the aerosol
the service life is the maximum number of cleaning or
concentration outside the barrier face covering to the aerosol
laundering cycles that can be applied to a reusable barrier face
concentration inside the barrier face covering on test subjects.
covering as specified by the manufacturer.
NOTE 7—Quantitative testing supplementing the barrier face covering
3.1.13 shelf life, n—in the specification of barrier face
leakage assessment represents the total inward leakage measured during
coverings, the length of time after the date of manufacture that
laboratory testing. During wearing of barrier face coverings outside the
a barrier face covering can be stored as specified by the
laboratory, leakage is a dynamic condition and may be greater or lesser. A
quantitative leakage assessment may not represent the likely outward manufacturer.
leakage of particles generated by the wearer because there are currently no
3.1.14 source control, n—the use of a barrier face covering
specific accepted techniques available to measure outward leakage from a
over the wearer’s nose and mouth that is intended to contain
barrier face covering or any other products. Thus, no claims may be made
with respect to the degree of source control offered by the barrier face the wearer’s respiratory secretions, including aerosols, to help
covering based on a quantitative leakage assessment.
prevent the transmission from infected individuals who may or
NOTE 8—A barrier face covering that rests directly on the nose and
may not have symptoms of a specific respiratory disease.
mouth is likely to have limited interior volume (that is, space between the
3.1.15 sub-micron particulate filtration effıciency, n—a mea-
barrier face covering and the nose and mouth). In this case, a quantitative
leakage assessment may not adequately measure inward aerosol leakage. sure of the ability of a barrier face covering to capture
F3502 − 24
aerosolized particles smaller than one micron, expressed as the percentage reduction that can range from 0 % (no sub-micron
percentage difference between the concentration of particles filtration capability) to 99.97 % (practically all sub-micron
that do not pass the barrier face covering versus the particle aerosols are blocked by the product). For the purpose of this
challenge concentration at a given face velocity for flat samples specification, a minimum 20 % requirement is set. This specific
or flow rate for whole article testing.
performance property provides a greater challenge than most
3.1.15.1 Discussion—In this specification, a specific form of other particulate filtration tests, including BFE, based on the
sub-micron particulate efficiency testing is performed as de-
use of smaller aerosols and more rigorous test conditions.
scribed in 8.1. This test method is based on NPPTL Standard
4.1.2 As filtration efficiency for a barrier face covering
Test Procedure TEB-APR-STP-0059 that involves the use of
increases, airflow resistance (breathing resistance) also
poly-disperse sodium chloride (NaCl) aerosols with a count
increases, making it more difficult to breathe. Consequently, a
median diameter of 75 6 20 nm diameter and a geometric
maximum airflow resistance for barrier face coverings is
standard deviation of ≤1.86 as measured with a suitable
established. Measurements of airflow resistance are made with
forward-light scattering photometer. In this testing, the filtra-
the same equipment that is used to measure sub-micron
tion efficiency is measured for either the barrier face covering
particulate filtration efficiency. This testing yields airflow
or those portions of the barrier face covering that cover the
resistance values in millimeters of water gauge pressure
wearer’s nose and mouth.
(mm H O), where lower pressures indicate easier breathing. In
3.1.16 supplier’s declaration of conformity (SDOC), n—a
this standard, the airflow resistance must be at 15 mm H O or
document by which a first-party or supplier conveys an
below. The value of 15 mm H O was chosen as this level is a
assurance that the object of conformity fulfills specified re-
lower breathing resistance than required for filtering facepiece
quirements.
respirators and is not expected to require a pre-use medical
evaluation for the general user population.
3.1.17 surgical N95 respirator, n—a respirator that has both
NIOSH approval as an N95 filtering facepiece respirator per 42 4.1.3 Measurements of sub-micron particulate filtration ef-
CFR Part 84 and FDA clearance as a Class II medical device ficiency and airflow resistance do not account for the leakage
under 21 CFR Section 878.4040. of air around the perimeter of the barrier face covering. A
leakage assessment using a design analysis of the product is
3.1.17.1 Discussion—Surgical N95 respirators are N95 fil-
tering facepiece respirators that are approved under 42 CFR required to assess the ability of the barrier face covering design
to provide appropriate coverage for a range of wearer faces of
Part 84 criteria and meet additional performance criteria for
material biocompatibility, fluid resistance, and flammability different dimensions. The design analysis can be conducted by
the manufacturer in a number of different ways. The specifi-
required by the FDA.
cation also permits the supplemental use of quantitative infor-
3.2 For definitions of other protective clothing-related terms
mation obtained from a modified form of Test Method F3407
used in this specification, refer to Terminology F1494.
using test subjects. This test yields a reportable ratio of outside
4. Significance and Use aerosol concentration to the concentration of aerosol in the
wearer’s breathing zone. Thus, an inward leakage ratio of 5.0
4.1 Barrier face coverings are worn over at least the nose
indicates the aerosol concentration outside the barrier face
and mouth with the primary purpose of providing source
covering is five times higher than the aerosol concentration
control and to potentially reduce inhaled aerosols. It is ex-
inside the barrier face covering. An inward leakage ratio of 1.0
pected that a range of barrier face covering products with
is the lowest possible result and represents that the inside and
different configurations, designs, and materials of construction
outside environments are at the same aerosol concentration.
can be developed and qualified in accordance with this
4.1.4 Additional testing requirements are included in this
specification. For this reason, a limited number of principal
specification for barrier face coverings that are intended to be
performance evaluations are applied. The principal perfor-
laundered or cleaned and reused. These tests evaluate the
mance requirements in this specification for barrier face
impact of multiple cycles of cleaning or laundering on sub-
coverings include sub-micron particle filtration efficiency and
micron particulate filtration efficiency, airflow resistance, and
airflow (breathing) resistance, with a separate design criterion
leakage assessment. This requirement is included in this
for leakage assessment.
specification because it is known that certain products may
4.1.1 Minimum requirements are set for sub-micron particu-
shrink, stretch, become distorted, or are otherwise negatively
late filtration efficiency for the purpose of source control. The
affected in their capabilities for source control and their
test for sub-micron particulate filtration efficiency is based on
potential for reducing the inhalation of aerosols. For the
42 CFR Part 84 (Subpart K), with further detail in NIOSH
purposes of this specification, defined performance require-
Standard Test Procedure TEB-APR-STP-0059. These proce-
ments for sub-micron particulate filtration efficiency and air-
dures are typically applied to air-purifying respirators with
flow resistance in addition to the leakage assessment design
filters. The test is performed using poly-disperse sodium
analysis requirements must be met after the maximum number
chloride (NaCl) aerosols with a count median diameter of 75 6
of laundering and cleaning cycles specified by the manufac-
20 nm electrical mobile diameter and a geometric standard
turer.
deviation of ≤1.86 to give a mass median aerodynamic
diameter of 0.3 μm. Testing is performed on full products or, 4.1.5 A system for reporting the key performance properties
for certain products, the area of the product that fully covers is established in this specification where compliant product
the wearer’s nose and mouth. Testing to this method yields a performance above the minimum levels is classified into two
F3502 − 24
NOTE 10—It is possible to assess these characteristics of barrier face
different levels that indicate differences of performance. The
covering materials by performing dermal irritation and skin sensitization
purpose of this classification system is to allow end users to
tests according to procedures provided in ISO/ANSI/AAMI 10993-10 and
differentiate products among the mandatory performance
by performing cytotoxicity testing per ISO/ANSI/AAMI 10993-5. This
properties—sub-micron particulate filtration efficiency and air-
note does not imply a requirement to use any of the listed tests or any
flow resistance. While the higher level indicates better perfor-
particular test for determining that the product does not irritate the wearer.
It is further possible that the use of materials already evaluated to these
mance for the individual property, these levels do not imply
standards satisfies this requirement. Manufacturers or material suppliers
specific protection levels or applications since there is currently
can demonstrate the absence of toxic materials by complying with
insufficient information to characterize how barrier face cov-
national, regional, or local requirements for the use of restricted sub-
ering performance relates to all conditions of use. It is also
stances. There are also commercial entities that provide services to verify
possible for a product to have high performance for one that materials, components, and products are free of restricted substances.
property (sub-micron particulate filtration efficiency or airflow
5.1.3 Barrier face coverings shall not be made of materials
resistance) and low performance for the other property.
that pose a flammability hazard.
5.1.3.1 Where barrier face coverings are used in applica-
4.2 Design criteria are established in this specification to
tions where flame, high heat, electrical arc, or other thermal
ensure the barrier face covering stays over the wearer’s nose
hazards are present, barrier face coverings shall be qualified to
and mouth, as well as to limit the use of features that would
the respective applicable standards, as appropriate.
compromise the effectiveness of the barrier face covering from
providing source control and reducing the inhalation of aero-
NOTE 11—Barrier face coverings made of textile fabrics are considered
sols. For example, the incorporation of vents, valves, or other
wearing apparel and are subject to 16 CFR 1610 requirements for the
measurement of textile material flammability. The application of this
features that allow for airflow to bypass the filtration elements
federal regulation is intended to limit the use of potentially dangerous,
of the barrier face covering during exhalation are prohibited.
flammable materials, where acceptable performance is judged by the
4.3 Minimum requirements are established for labeling of respective materials being classified as Class 1, “Normal Flammability,”
Class 2, “Intermediate Flammability,” or exempt from testing. Specific
barrier face coverings and for information provided by the
standards related to flame, high heat, electrical arc, and other thermal
manufacturer to the end user. The intent of these requirements
hazard exposures include, but are not limited to: Specification F1506,
is to deliver products that are clearly identified as meeting this
Specification F2302, and NFPA 2112.
specification and that additional pertinent information and
5.1.4 Barrier face coverings shall be free of any sharp edges,
instructions are provided to the end user.
sharp points, or burrs.
4.4 The conformity assessment requirements for barrier face
5.1.5 Barrier face coverings shall be permitted to be either
coverings in this specification have been established to provide
disposable (single use) or reusable (multiple uses). Barrier face
confidence that the products labeled as compliant meet all
covering designs that combine disposable and reusable parts
applicable criteria of this specification. The specification for
shall meet the requirement in 5.1.8.
sub-micron particulate filtration efficiency and airflow resis-
5.1.5.1 Barrier face coverings shall be constructed of mate-
tance performance requirements must be conducted by labora-
rials and designed such that they will not be damaged by
tories accredited to ISO/IEC 17025, and the testing performed
ordinary handling, donning, and doffing.
must be within the scope of the laboratory’s ISO/IEC 17025
5.1.5.2 Barrier face coverings that are intended to be reus-
accreditation.
able shall be constructed of materials and designed such that
they will not be damaged by ordinary handling, donning, and
4.5 It is the responsibility of the user of this specification to
doffing after being repeatedly subjected to laundering or
establish appropriate safety and health practices and to deter-
cleaning as specified by the manufacturer.
mine the applicability of regulatory limitations prior to use.
NOTE 12—Section 6 has specific requirements for evaluating the
4.6 A number of recommendations are provided through
performance of reusable barrier face coverings for their continued
notes to aid in the clarification of requirements or suggestions
performance following the manufacturer’s recommended maximum num-
to address other areas of compliance with this specification.
ber of laundering (or cleaning) cycles when using the manufacturer’s
recommended laundering or cleaning procedures.
5. Design Requirements
5.1.6 Barrier face coverings shall be designed, shaped, or
have features that aid in reducing the flow of air around the
5.1 General Construction:
perimeter of the product.
5.1.1 The barrier face covering shall be designed to cover at
least the wearer’s nose and mouth and fit snugly where the 5.1.7 Barrier face coverings shall not have vents, valves, or
other open pathways as part of their design.
product contacts the wearer’s face to reduce gaps, as deter-
mined by the product design analysis in 5.4.
NOTE 13—The use of exhalation valves or other features that bypass the
filtration of the product are not allowed because these features potentially
NOTE 9—A design analysis is required per 5.4 to assess potential
diminish source control and increase the likelihood of unfiltered air to pass
leakage through or around the barrier face covering. The general approach
through into the environment.
used in the design analysis is described by the manufacturer as part of the
report. This can be supplemented by reporting the results of quantitative
5.1.8 Barrier face coverings with replaceable filters shall
testing as specified in 8.3.
have means for reducing the likelihood of improper filter
5.1.2 Portions of the barrier face covering materials that placement in the product. Where these configurations exist, the
contact the wearer’s skin shall be made of non-irritating and manufacturer shall provide specific instructions that address
nontoxic materials. the use and care of their products relative to filter replacement
F3502 − 24
and disposal of filtering components or cleaning/laundering of declaration. When used, the leakage ratio shall be determined
reusable parts of the barrier face covering. using Test Method F3407, with the modifications specified in
5.1.9 Barrier face coverings shall be permitted to include 8.3.
transparent materials for the purpose of allowing others to view 5.4.3 Where barrier face coverings are reusable and in-
the wearer’s lips, but these configurations are still required to tended for laundering or cleaning, the product design analysis
meet the performance requirements of Section 6 where the shall be applied to barrier face coverings both in a new
transparent portions of the barrier face coverings are part of the condition and after the maximum number of laundering or
tested samples. cleaning cycles as specified by the manufacturer according to
the manufacturer’s care instructions.
5.2 Retention System:
5.2.1 Barrier face coverings shall have a means for keeping
NOTE 16—Examples of different means to accomplish a leakage
assessment includes dimensional analysis or computer modeling where
the barrier face covering over the wearer’s nose and mouth for
the product design is electronically captured and then compared to how
the expected period of use and range of activities.
the product can be placed on computer-generated faces of varying
NOTE 14—Examples of retention systems include, but are not limited dimensions. An alternative approach is to physically place barrier face
to: ties, elastic ear loops, and head harnesses. In some cases where the coverings on standardized head or head/torso forms (such as those
specified in ISO 16900-5) and judge their respective areas of coverage and
retention system is integrated with the filtering area, such as tubular neck
garments (sometimes referred to as gaiters), the area intended to cover the visually observe (or measure) any gaps between the barrier face covering
perimeter and underlying face portions of the head or head-torso form.
wearer’s nose and mouth must be clearly identifiable and proper orienta-
tion described in the user instructions. The effectiveness of these systems However, it is important to point out that the absence or existence of visual
gaps may not be truly indicative of whether leakage is likely or not. It is
for keeping the barrier face covering on the wearer’s head and maintaining
coverage of wearer’s nose and mouth varies with the type of retention also possible to apply this approach to a number of human subjects
representing a range of facial dimensions such as those described in
system in combination with the materials of construction and the overall
design. Subsection 5.4 includes an assessment as a degree for how well the Appendix X1. AATCC M14-2020 is an additional reference for evaluating
conformity of the barrier face covering on respective wearers providing
barrier face covering fits on individuals’ faces. For adult products, the use
of plastic toggles or slides is permitted but should not be able to release appropriate coverage with gaps that could result in leakage.
from the tie or free end (thus leaving the ability of the mask to fall open).
5.5 Accessories:
5.2.2 Where the barrier face covering uses a head harness,
5.5.1 Where accessories are provided that include but are
the head harness shall provide for adjustment to allow proper
not limited to braces or similar devices that affect the leakage
fit on the wearer’s head. When the head harness is made from
design analysis and quantitative testing of barrier face
elastic materials, the elasticity of the harness material is
coverings, these items shall be explicitly disclosed in the test
considered adequate adjustability for proper use.
report and described as part of the user instructions provided by
the product manufacturer as required in Section 11.
5.3 Sizing:
5.3.1 Where intended to be worn by a range of individuals,
6. Performance Requirements
multiple sizes shall be permitted, but not required, to allow a
6.1 Barrier face coverings shall meet the requirements
single model to fit a wide variety of the end user population,
excluding very young children (<2 years). Different sizing for specified in Table 1.
children versus adults is permitted.
6.2 Where the barrier face covering is reusable and intended
5.3.2 Barrier face coverings shall be permitted to be offered
to be laundered or cleaned, barrier face coverings shall meet
in single sizes for the general population and for specific
each of the requirements in Table 1, both in a new condition
population groups such as children.
and after the maximum number of laundering or cleaning
cycles specified for the product in accordance with 7.3.
NOTE 15—Anthropometric data for adult populations from the National
Institute for Occupational Safety and Health are available as a resource for
product size development. For the date of this specification, there were no 7. Sampling and Conditioning
known human subject panels for children’s sizes.
7.1 Type of Samples—Testing shall be performed on com-
5.4 Leakage Assessment:
plete barrier face coverings or materials as specified in each
5.4.1 The leakage assessment shall be reported by the
individual test method in Section 8.
manufacturer as part of the supplier’s declaration of conformity
7.1.1 Where materials are specified as the samples in the
(see Section 12).
individual test method, these samples shall be taken from
5.4.2 As part of its declaration, the manufacturer shall report
complete barrier face coverings unless the nature of the testing
that the product reduces leakage around the perimeter or other
requires larger samples than what can be obtained from any
areas of the barrier face covering based upon an analysis of the
particular finished product.
product design.
5.4.2.1 The manufacturer is permitted to conduct quantita-
TABLE 1 Barrier Face Covering Minimum Performance
tive testing to supplement its product design analysis self-
Requirements
Test Method
Performance Property Criteria
The report, “A Head-and-Face Anthropometric Survey of U.S. Respirator
Section
Users,” is available from Journal of Occupational and Environmental Hygiene, Vol
Sub-micron particulate filtration $20 % 8.1
2, No. 11, 2005, pp. 567–76. DOI: 10.1080/15459620500324727. https://
efficiency
www.nap.edu/resource/11815/Anthrotech_report.pdf. This report provides key fa-
cial dimensions for persons aged 18 to 55. This report may not address the full range Airflow resistance, inhalation #15 mm H O 8.2
of adult facial dimensions for all populations.
F3502 − 24
7.1.2 Where barrier face coverings include embellishments manufacturer, according to manufacturer care instructions (ten
such as logos, emblems, embossed lines, or other additive specimens tested in each condition for a total of 20 samples).
features for appearance purposes, sample selection shall ac-
8.1.1.3
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: F3502 − 23a F3502 − 24
Standard Specification for
Barrier Face Coverings
This standard is issued under the fixed designation F3502; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
INTRODUCTION
This is the first ASTM standard to address this type of product. The standard was primarily
established in response to the global COVID-19 pandemic beginning in 2019 to address a product that
is neither a medical face mask per ASTM Specification F2100 for providing source control, nor a
respirator for providing inhalation protection as defined by regulatory requirements specified in the
United States under 42 CFR Part 84.
This specification is intended to establish a national standard baseline for a source control device.
This standard brings value by specifying minimum design, performance, and testing requirements and
allowing comparison of products by end users where current guidelines have been limited. Evolving
literature suggests that barrier face coverings could reduce the potential for disease transmission, as
well as offering a reduction of inhalation particulate matter by the wearer. The focus of this
specification is to identify how the device should perform in terms of source control/protection,
comfort, and reuse potential. The level of source control/protection depends on how well particles are
blocked from going through the barrier face covering and minimizing the amount of leakage that may
occur around the perimeter of the barrier face covering. The specific performance property for
filtration efficiency provides a greater challenge than most other particulate filtration tests, including
BFE, based on the use of smaller particles and more rigorous test conditions. Barrier face coverings
must be comfortable enough for individuals to be willing to wear them for long periods of time.
Requirements for breathing resistance were incorporated into the specification. The final performance
criterion was the potential for reuse of the barrier face covering, so the possibility of reuse was
identified in the specification.
Users of this standard are directed to Section 1 (Scope) and Section 4 (Significance and Use) to
understand the specific areas addressed by this standard and its limitations, along with the reasons for
choice of specific requirements. Users of this standard are further directed to the specific caveats for
this standard that are included in 1.3 – 1.11. The subcommittee responsible for this standard intends
to further evolve this specification for addressing new knowledge about disease transmission reduction
and barrier face covering design, performance, labeling, conformity assessment, and other aspects of
these products’ safety, health, and environmental impact as this information becomes available.
1. Scope
1.1 This specification is intended to help ensure barrier face coverings meeting the stated requirements provide (1) a means of
source control for individual wearers by reducing expelled aerosols from the wearer’s nose and mouth into the air; and (2) a degree
of particulate filtration that potentially reduces the amount of aerosols inhaled by the wearer.
This specification is under the jurisdiction of ASTM Committee F23 on Personal Protective Clothing and Equipment and is the direct responsibility of Subcommittee
F23.65 on Respiratory.
Current edition approved April 1, 2023Feb. 1, 2024. Published April 2023March 2024. Originally approved in 2021. Last previous edition approved in 2023 as
F3502 – 23.F3502 – 23a. DOI: 10.1520/F3502-23A.10.1520/F3502-24.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
F3502 − 24
NOTE 1—The source control/protection provided by barrier face coverings depends on several factors not considered in this specification, such as material
degradation from wearer challenges including perspiration, talking, sneezing, and the length of time the barrier face covering is worn. Further research
is needed to expand the evidence base for the protective effect of face coverings and, in particular, to identify the combinations of materials that maximize
both their blocking and filtering effectiveness, as well as fit, comfort, durability, and consumer appeal. (https://www.cdc.gov/coronavirus/2019-ncov/
more/masking-science-sars-cov2.html.)
NOTE 2—There are currently no established methods for measuring outward leakage from a barrier face covering, medical mask, or respirator. Nothing
in this specification addresses or implies a quantitative assessment of outward leakage and no claims can be made about the degree to which a barrier
face covering reduces expired human-generated aerosols.
1.2 This specification establishes minimum design, performance (testing), labeling, user instruction, reporting and classification,
and conformity assessment requirements for barrier face coverings.
1.2.1 Design criteria include setting minimum areas of face coverage over the wearer’s nose and mouth, prohibiting open vents
or valves, requiring a means for retaining the barrier face covering on the wearer’s head, and providing a representation of product
sizing. Manufacturers are further required to perform a design analysis for assessing leakage of exhaled air from the barrier face
covering where the general approach is described in the product report. Manufacturers are permitted to conduct quantitative testing
as specified in this specification to supplement the design analysis. Accessories, such as braces or other devices that allow the
barrier face covering to better conform to the wearer’s face, are addressed as part of this specification if used for the purpose of
reducing leakage.
1.2.2 Performance and testing criteria define minimum barrier face covering filtration efficiency and airflow resistance
performance properties. Sub-micron particulate filtration efficiency represents the ability to capture and reduce respirable aerosols
that potentially contain viruses and bacteria. Airflow resistance represents the wearer’s ease of breathing or breathability while
wearing the barrier face covering. The impact of repeated cleaning or laundering on continued performance is applied for
measuring performance properties for those barrier face coverings that are intended for reuse. Manufacturers are permitted to also
provide test results for bacterial filtration efficiency (BFE) as supplemental information to the mandatory performance
measurement of sub-micron particulate filtration efficiency.
NOTE 3—The principal performance criteria for barrier face covering determined by testing are sub-micron particle filtration efficiency and airflow
resistance. Quantitative leakage assessment testing is optional for information purposes and is not required. This testing is not likely to be representative
of outward leakage from the barrier face covering and should not be claimed to represent the amount of source control offered by the face covering.
Bacterial filtration efficiency testing is also optional and not required. It is significantly different than sub-micron filtration efficiency, and the results of
BFE testing cannot be interchanged or directly compared.
1.2.3 Labeling requirements specify the minimum content for labels that appear on the barrier face covering, its immediate
packaging, and if different, point-of-sale packaging.
1.2.4 User instructions are required to guide selection and sizing, proper use (positioning and adjustment), and care including
cleaning or laundering if product reuse is intended; inform on product cautions and limitations; and describe product replacement
and disposal procedures.
1.2.5 Conformity assessment is demonstrated with a Supplier Declaration of Conformity (SDOC) following Guide F3050, Annex
A3, Model A. The SDOC states that each barrier face covering labeled as compliant has met all of the requirements of this
specification including design criteria, performance criteria, test methods, labeling, and user information. Additionally,
conformance to this specification requires that sub-micron particulate filtration efficiency and airflow resistance tests have been
performed by a laboratory accredited for conducting these tests.
NOTE 4—This specification does not provide for any form of provisional, limited, or partial conformance of barrier face coverings since their compliance
with this specification is a function of meeting all performance requirements, including specific filtration efficiency and breathability requirements, as well
as all applicable design, labeling, reporting, and user information requirements.
1.3 This specification addresses barrier face coverings that are either disposable or reusable.
1.4 This specification does not address the unique additional performance attributes of barrier face coverings that exist for certain
applications, such as flame-resistant apparel used in environments where there are flame, high heat, electrical arc, or related
hazards, but does recommend that barrier face coverings also conform to other standards as applicable.
F3502 − 24
1.5 This specification does not address the use of antimicrobial or antiviral materials, finishes, or mechanisms, nor the use of drugs,
biologics, or nanoparticles in barrier face coverings. This specification also does not address the efficacy of cleaning agents or other
chemicals for cleaning, disinfecting, or sanitizing barrier face coverings.
NOTE 5—Claims made about the use of antimicrobial materials, finishes, or mechanisms; or the use of drugs, biologics, or nanoparticles in any product
subject the manufacturer to regulatory oversight by government agencies, including the U.S. Food and Drug Administration in the United States, which
applies additional safety and efficacy requirements to these products. See 5.1.2 for the requirement of nontoxic and non-irritating materials used in the
construction of barrier face coverings.
1.6 This specification does not address requirements for medical face masks, which are covered in Specification F2100.
1.7 Nothing in this specification is intended to contradict or replace criteria that are established in 42 CFR Part 84 for air-purifying
respirators or requirements for use of respirators in accordance with 29 CFR 1910.134.
1.8 Nothing in this specification is intended to imply that barrier face coverings qualify as approved respiratory protection devices
or have FDA clearance for use in a healthcare setting.
1.9 Nothing in this specification is intended to imply that barrier face coverings should be placed on very young children (<2
years), anyone who has trouble breathing, or anyone who is unconscious, incapacitated, or otherwise unable to remove barrier face
coverings without assistance.
1.10 The values stated in SI units or in other units shall be regarded separately as standard. The values stated in each system must
be used independently of the other, without combining values in any way.
NOTE 6—There are several aspects that relate to the material composition and design of barrier face coverings that are not addressed in this specification
but warrant attention relative to their safety, health effects, and impact on the environment, including but not limited to: leaching of potentially toxic
finishes, inhalable toxic substances from materials, and bioburden inhibitors subject to regulatory oversight.
1.11 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of
regulatory limitations prior to use.
1.12 This international standard was developed in accordance with internationally recognized principles on standardization
established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued
by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2. Referenced Documents
2.1 ASTM Standards:
D3938 Guide for Determining or Confirming Care Instructions for Apparel and Other Textile Products
D5489 Guide for Care Symbols for Care Instructions on Textile Products
F1494 Terminology Relating to Protective Clothing
F1506 Performance Specification for Flame Resistant and Electric Arc Rated Protective Clothing Worn by Workers Exposed to
Flames and Electric Arcs
F2100 Specification for Performance of Materials Used in Medical Face Masks
F2101 Test Method for Evaluating the Bacterial Filtration Efficiency (BFE) of Medical Face Mask Materials, Using a Biological
Aerosol of Staphylococcus aureus
F2302 Performance Specification for Labeling Protective Clothing Which Provides Resistance to Incidental Exposures to Heat
or Open Flame
F3050 Guide for Conformity Assessment of Personal Protective Clothing and Equipment
F3407 Test Method for Respirator Fit Capability for Negative-Pressure Half-Facepiece Particulate Respirators
2.2 AATCC Monograph:
M14 Guidance and Considerations for General Purpose Textile Face Coverings: Adult
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Available from American Association of Textile Chemists and Colorists (AATCC), P.O. Box 12215, Research Triangle Park, NC 27709-2215, http://www.aatcc.org.
F3502 − 24
2.3 ANSI/ASQC Standard:
ANSI/ASQC Z1.4 Sampling Procedures and Tables for Inspection by Attributes
2.4 ISO Standards:
ISO 2859-1 Sampling Procedures for Inspection by Attributes—Part 1: Sampling Schemes Indexed by Acceptance Quality Limit
(AQL) for Lot-by-Lot Inspection
ISO/ANSI/AAMI 10993-5 Biological Evaluation of Medical Devices—Part 5: Tests for In Vitro Cytotoxicity
ISO/ANSI/AAMI 10993-10 Biological Evaluation of Medical Devices—Part 10: Tests for Irritation and Skin Sensitization
ISO 16900-5 Respiratory Protective Devices—Methods of Test and Test Equipment—Part 5: Breathing Machine, Metabolic
Simulator, RPD Headforms and Torso, Tools and Verification Tools
ISO/IEC 17025 General Requirements for the Competence of Testing and Calibration Laboratories
2.5 Federal Regulations:
16 CFR Part 1610 Standard for the Flammability of Clothing Textiles
16 CFR Part 303 Rules and Regulations Under the Textile Fiber Products Identification Act
16 CFR Part 423 Care Labeling of Textile Wearing Apparel and Certain Piece Goods as Amended
29 CFR 1910.134 Respiratory Protection
42 CFR Part 84 Approval of Respiratory Protective Devices
2.6 NPPTL Standard Test Procedure:
TEB-APR-STP-0059 Determination of Particulate Filter Efficiency Level for N95 Series Filters Against Solid Particulates for
Non-Powered, Air-Purifying Respirators
2.7 NFPA Standard:
NFPA 2112 Standard on Flame-Resistant Clothing for Protection of Industrial Personnel Against Short-Duration Thermal
Exposures from Fire
3. Terminology
3.1 Definitions:
3.1.1 aerosol, n—a suspension of solid or liquid particulate matter in a gas.
3.1.2 airflow resistance, n—in the testing of a barrier face covering, the measured pressure drop across the barrier face covering
under specified test conditions.
3.1.2.1 Discussion—
This specification involves measuring airflow resistance of the barrier face covering during initial portion of sub-micron particulate
filtration efficiency test for which specific sample mounting and airflow conditions are set.
3.1.3 bacterial filtration effıciency (BFE), n—the effectiveness of a material in preventing the passage of aerosolized bacteria,
expressed as the percentage of a known quantity that does not pass through the barrier face covering at a given aerosol flow rate.
3.1.3.1 Discussion—
In this specification, BFE is only an optional reported test and not part of the requirements. BFE testing primarily involves the
evaluation of larger sized particles and lower exposure conditions as compared to sub-micron particulate filtration efficiency.
3.1.4 barrier face covering, n—a product worn on the face, specifically covering at least the wearer’s nose and mouth, with the
primary purpose of providing source control and to provide a degree of particulate filtration to reduce the amount of inhaled
aerosols.
3.1.4.1 Discussion—
In this specification, barrier face coverings are assessed for airflow resistance; filtration performance using sub-micron particulate
filtration efficiency testing; and the degree of face coverage per a leakage assessment using a product design analysis that can be
supplemented by quantitative testing using test subjects.
3.1.5 conformity assessment, n—demonstration that specified requirements relating to a product, process, system, person, or body
have been fulfilled. F3050
Available from American Society for Quality (ASQ), 600 N. Plankinton Ave., Milwaukee, WI 53203, http://www.asq.org.
Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http://www.ansi.org.
Available from U.S. Government Printing Office, Superintendent of Documents, 732 N. Capitol St., NW, Washington, DC 20401-0001, http://www.access.gpo.gov.
Available from National Personal Protective Technology Laboratory (NPPTL), https://www.cdc.gov/niosh/npptl/stps/pdfs/TEB-APR-STP-0059-508.pdf.
Available from National Fire Protection Association (NFPA), 1 Batterymarch Park, Quincy, MA 02169-7471, http://www.nfpa.org.
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3.1.6 design analysis, n—a process intended to verify that the barrier face covering provides coverage of at least the wearer’s nose
and mouth and to identify potential leakage pathways in the design of a barrier face covering as worn by an intended population.
3.1.6.1 Discussion—
In this specification, a design analysis is used by the manufacturer for assessing the coverage provided and leakage associated with
a barrier face covering when worn by the intended user population. A design analysis does not provide quantitative measurements
of leakage around the perimeter of the barrier face covering.
3.1.7 flammability, n—a quality of a product related to its rate of flame spread when contacted by a flame source.
3.1.7.1 Discussion—
In this specification, flammability applies to barrier face coverings as determined by 16 CFR Part 1610 as part of the Consumer
Product Safety Commission regulations for wearing apparel. However, products that comply with these regulations by having
Class 1 or 2 flammability are considered not flame resistant when exposed to flame, high heat, electrical arc, or other thermal
hazards.
3.1.8 leakage assessment, n—the evaluation of a barrier face covering for its potential to fit the wearer’s face by at least covering
their nose and mouth and to reduce the likelihood of leakage of unfiltered air between the wearer and the outside environment.
3.1.8.1 Discussion—
In this specification, the leakage assessment addresses the potential for aerosol passing around the perimeter of the barrier face
covering and applies to both inward and outward leakage. When quantitative testing is performed according to 8.3, the leakage
assessment will also include the measurement of any aerosol that passes through the barrier face covering. This quantitative testing
measures inward leakage that is presented as the ratio of the aerosol concentration outside the barrier face covering to the aerosol
concentration inside the barrier face covering on test subjects.
NOTE 7—Quantitative testing supplementing the barrier face covering leakage assessment represents the total inward leakage measured during laboratory
testing. During wearing of barrier face coverings outside the laboratory, leakage is a dynamic condition and may be greater or lesser. A quantitative
leakage assessment may not represent the likely outward leakage of particles generated by the wearer because there are currently no specific accepted
techniques available to measure outward leakage from a barrier face covering or any other products. Thus, no claims may be made with respect to the
degree of source control offered by the barrier face covering based on a quantitative leakage assessment.
NOTE 8—A barrier face covering that rests directly on the nose and mouth is likely to have limited interior volume (that is, space between the barrier face
covering and the nose and mouth). In this case, a quantitative leakage assessment may not adequately measure inward aerosol leakage.
3.1.9 medical face mask, n—an item of protective clothing designed to protect portions of the wearer’s face, including the mucous
membrane areas of the wearer’s nose and mouth, from contact with blood and other body fluids during medical procedures.
3.1.9.1 Discussion—
Medical face masks include surgical masks, procedure masks, isolation masks, laser masks, dental masks, and patient care masks.
Isolation masks, laser masks, dental masks, and patient care masks are considered isolation masks. For many user groups, the term
“mask” has become synonymous with any product worn on the wearer’s face that offers a level of filtration efficiency; however,
in the context of this specification, “mask” refers only to medical face masks that are different from barrier face coverings.
Requirements for medical face masks are provided in Specification F2100. This specification is not intended to address regulatory
requirements.
3.1.10 respirator, n—personal protective equipment (PPE) designed to protect the wearer from inhalation of hazardous
contaminants.
3.1.10.1 Discussion—
Barrier face coverings are not designed to meet the performance requirements of NIOSH-approved respirators. For the purpose of
this specification, healthcare workers are typically instructed to wear filtering facepiece respirators with N95 or higher levels of
filtration efficiency as defined in 42 CFR Part 84 that are intended to protect the wearer from exposure to pathogenic biological
aerosols. See also the definition for surgical N95 respirators.
3.1.11 reusable, adj—referring to the ability of a product to be used and laundered or cleaned multiple times and maintain its
specified performance characteristics.
3.1.11.1 Discussion—
The use of the term “reusable” in this specification is intended to distinguish types of barrier face coverings that are durable and
that can be further subjected to laundering or cleaning which permits their use multiple times until they are damaged, cannot be
effectively cleaned, or have surpassed the expiration date or are beyond the manufacturer’s designated service life.
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3.1.12 service life, n—in the specification of barrier face coverings, the maximum number of use and laundering or cleaning cycles
that barrier face coverings can undergo and still maintain their performance properties.
3.1.12.1 Discussion—
For the purpose of this specification, the service life is the maximum number of cleaning or laundering cycles that can be applied
to a reusable barrier face covering as specified by the manufacturer.
3.1.13 shelf life, n—in the specification of barrier face coverings, the length of time after the date of manufacture that a barrier
face covering can be stored as specified by the manufacturer.
3.1.14 source control, n—the use of a barrier face covering over the wearer’s nose and mouth that is intended to contain the
wearer’s respiratory secretions, including aerosols, to help prevent the transmission from infected individuals who may or may not
have symptoms of a specific respiratory disease.
3.1.15 sub-micron particulate filtration effıciency, n—a measure of the ability of a barrier face covering to capture aerosolized
particles smaller than one micron, expressed as the percentage difference between the concentration of particles that do not pass
the barrier face covering versus the particle challenge concentration at a given face velocity for flat samples or flow rate for whole
article testing.
3.1.15.1 Discussion—
In this specification, a specific form of sub-micron particulate efficiency testing is performed as described in 8.1. This test method
is based on NPPTL Standard Test Procedure TEB-APR-STP-0059 that involves the use of poly-disperse sodium chloride (NaCl)
aerosols with a count median diameter of 75 6 20 nm diameter and a geometric standard deviation of ≤1.86 as measured with a
suitable forward-light scattering photometer. In this testing, the filtration efficiency is measured for either the barrier face covering
or those portions of the barrier face covering that cover the wearer’s nose and mouth.
3.1.16 supplier’s declaration of conformity (SDOC), n—a document by which a first-party or supplier conveys an assurance that
the object of conformity fulfills specified requirements.
3.1.17 surgical N95 respirator, n—a respirator that has both NIOSH approval as an N95 filtering facepiece respirator per 42 CFR
Part 84 and FDA clearance as a Class II medical device under 21 CFR Section 878.4040.
3.1.17.1 Discussion—
Surgical N95 respirators are N95 filtering facepiece respirators that are approved under 42 CFR Part 84 criteria and meet additional
performance criteria for material biocompatibility, fluid resistance, and flammability required by the FDA.
3.2 For definitions of other protective clothing-related terms used in this specification, refer to Terminology F1494.
4. Significance and Use
4.1 Barrier face coverings are worn over at least the nose and mouth with the primary purpose of providing source control and
to potentially reduce inhaled aerosols. It is expected that a range of barrier face covering products with different configurations,
designs, and materials of construction can be developed and qualified in accordance with this specification. For this reason, a
limited number of principal performance evaluations are applied. The principal performance requirements in this specification for
barrier face coverings include sub-micron particle filtration efficiency and airflow (breathing) resistance, with a separate design
criterion for leakage assessment.
4.1.1 Minimum requirements are set for sub-micron particulate filtration efficiency for the purpose of source control. The test for
sub-micron particulate filtration efficiency is based on 42 CFR Part 84 (Subpart K), with further detail in NIOSH Standard Test
Procedure TEB-APR-STP-0059. These procedures are typically applied to air-purifying respirators with filters. The test is
performed using poly-disperse sodium chloride (NaCl) aerosols with a count median diameter of 75 6 20 nm electrical mobile
diameter and a geometric standard deviation of ≤1.86 to give a mass median aerodynamic diameter of 0.3 μm. Testing is performed
on full products or, for certain products, the area of the product that fully covers the wearer’s nose and mouth. Testing to this
method yields a percentage reduction that can range from 0 % (no sub-micron filtration capability) to 99.97 % (practically all
sub-micron aerosols are blocked by the product). For the purpose of this specification, a minimum 20 % requirement is set. This
specific performance property provides a greater challenge than most other particulate filtration tests, including BFE, based on the
use of smaller aerosols and more rigorous test conditions.
4.1.2 As filtration efficiency for a barrier face covering increases, airflow resistance (breathing resistance) also increases, making
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it more difficult to breathe. Consequently, a maximum airflow resistance for barrier face coverings is established. Measurements
of airflow resistance are made with the same equipment that is used to measure sub-micron particulate filtration efficiency. This
testing yields airflow resistance values in millimeters of water gauge pressure (mm H O), where lower pressures indicate easier
breathing. In this standard, the airflow resistance must be at 15 mm H O or below. The value of 15 mm H O was chosen as this
2 2
level is a lower breathing resistance than required for filtering facepiece respirators and is not expected to require a pre-use medical
evaluation for the general user population.
4.1.3 Measurements of sub-micron particulate filtration efficiency and airflow resistance do not account for the leakage of air
around the perimeter of the barrier face covering. A leakage assessment using a design analysis of the product is required to assess
the ability of the barrier face covering design to provide appropriate coverage for a range of wearer faces of different dimensions.
The design analysis can be conducted by the manufacturer in a number of different ways. The specification also permits the
supplemental use of quantitative information obtained from a modified form of Test Method F3407 using test subjects. This test
yields a reportable ratio of outside aerosol concentration to the concentration of aerosol in the wearer’s breathing zone. Thus, an
inward leakage ratio of 5.0 indicates the aerosol concentration outside the barrier face covering is five times higher than the aerosol
concentration inside the barrier face covering. An inward leakage ratio of 1.0 is the lowest possible result and represents that the
inside and outside environments are at the same aerosol concentration.
4.1.4 Additional testing requirements are included in this specification for barrier face coverings that are intended to be laundered
or cleaned and reused. These tests evaluate the impact of multiple cycles of cleaning or laundering on sub-micron particulate
filtration efficiency, airflow resistance, and leakage assessment. This requirement is included in this specification because it is
known that certain products may shrink, stretch, become distorted, or are otherwise negatively affected in their capabilities for
source control and their potential for reducing the inhalation of aerosols. For the purposes of this specification, defined performance
requirements for sub-micron particulate filtration efficiency and airflow resistance in addition to the leakage assessment design
analysis requirements must be met after the maximum number of laundering and cleaning cycles specified by the manufacturer.
4.1.5 A system for reporting the key performance properties is established in this specification where compliant product
performance above the minimum levels is classified into two different levels that indicate differences of performance. The purpose
of this classification system is to allow end users to differentiate products among the mandatory performance properties—sub-
micron particulate filtration efficiency and airflow resistance. While the higher level indicates better performance for the individual
property, these levels do not imply specific protection levels or applications since there is currently insufficient information to
characterize how barrier face covering performance relates to all conditions of use. It is also possible for a product to have high
performance for one property (sub-micron particulate filtration efficiency or airflow resistance) and low performance for the other
property.
4.2 Design criteria are established in this specification to ensure the barrier face covering stays over the wearer’s nose and mouth,
as well as to limit the use of features that would compromise the effectiveness of the barrier face covering from providing source
control and reducing the inhalation of aerosols. For example, the incorporation of vents, valves, or other features that allow for
airflow to bypass the filtration elements of the barrier face covering during exhalation are prohibited.
4.3 Minimum requirements are established for labeling of barrier face coverings and for information provided by the manufacturer
to the end user. The intent of these requirements is to deliver products that are clearly identified as meeting this specification and
that additional pertinent information and instructions are provided to the end user.
4.4 The conformity assessment requirements for barrier face coverings in this specification have been established to provide
confidence that the products labeled as compliant meet all applicable criteria of this specification. The specification for sub-micron
particulate filtration efficiency and airflow resistance performance requirements must be conducted by laboratories accredited to
ISO/IEC 17025, and the testing performed must be within the scope of the laboratory’s ISO/IEC 17025 accreditation.
4.5 It is the responsibility of the user of this specification to establish appropriate safety and health practices and to determine the
applicability of regulatory limitations prior to use.
4.6 A number of recommendations are provided through notes to aid in the clarification of requirements or suggestions to address
other areas of compliance with this specification.
5. Design Requirements
5.1 General Construction:
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5.1.1 The barrier face covering shall be designed to cover at least the wearer’s nose and mouth and fit snugly where the product
contacts the wearer’s face to reduce gaps, as determined by the product design analysis in 5.4.
NOTE 9—A design analysis is required per 5.4 to assess potential leakage through or around the barrier face covering. The general approach used in the
design analysis is described by the manufacturer as part of the report. This can be supplemented by reporting the results of quantitative testing as specified
in 8.3.
5.1.2 Portions of the barrier face covering materials that contact the wearer’s skin shall be made of non-irritating and nontoxic
materials.
NOTE 10—It is possible to assess these characteristics of barrier face covering materials by performing dermal irritation and skin sensitization tests
according to procedures provided in ISO/ANSI/AAMI 10993-10 and by performing cytotoxicity testing per ISO/ANSI/AAMI 10993-5. This note does
not imply a requirement to use any of the listed tests or any particular test for determining that the product does not irritate the wearer. It is further possible
that the use of materials already evaluated to these standards satisfies this requirement. Manufacturers or material suppliers can demonstrate the absence
of toxic materials by complying with national, regional, or local requirements for the use of restricted substances. There are also commercial entities that
provide services to verify that materials, components, and products are free of restricted substances.
5.1.3 Barrier face coverings shall not be made of materials that pose a flammability hazard.
5.1.3.1 Where barrier face coverings are used in applications where flame, high heat, electrical arc, or other thermal hazards are
present, barrier face coverings shall be qualified to the respective applicable standards, as appropriate.
NOTE 11—Barrier face coverings made of textile fabrics are considered wearing apparel and are subject to 16 CFR 1610 requirements for the measurement
of textile material flammability. The application of this federal regulation is intended to limit the use of potentially dangerous, flammable materials, where
acceptable performance is judged by the respective materials being classified as Class 1, “Normal Flammability,” Class 2, “Intermediate Flammability,”
or exempt from testing. Specific standards related to flame, high heat, electrical arc, and other thermal hazard exposures include, but are not limited to:
Specification F1506, Specification F2302, and NFPA 2112.
5.1.4 Barrier face coverings shall be free of any sharp edges, sharp points, or burrs.
5.1.5 Barrier face coverings shall be permitted to be either disposable (single use) or reusable (multiple uses). Barrier face
covering designs that combine disposable and reusable parts shall meet the requirement in 5.1.8.
5.1.5.1 Barrier face coverings shall be constructed of materials and designed such that they will not be damaged by ordinary
handling, donning, and doffing.
5.1.5.2 Barrier face coverings that are intended to be reusable shall be constructed of materials and designed such that they will
not be damaged by ordinary handling, donning, and doffing after being repeatedly subjected to laundering or cleaning as specified
by the manufacturer.
NOTE 12—Section 6 has specific requirements for evaluating the performance of reusable barrier face coverings for their continued performance following
the manufacturer’s recommended maximum number of laundering (or cleaning) cycles when using the manufacturer’s recommended laundering or
cleaning procedures.
5.1.6 Barrier face coverings shall be designed, shaped, or have features that aid in reducing the flow of air around the perimeter
of the product.
5.1.7 Barrier face coverings shall not have vents, valves, or other open pathways as part of their design.
NOTE 13—The use of exhalation valves or other features that bypass the filtration of the product are not allowed because these features potentially diminish
source control and increase the likelihood of unfiltered air to pass through into the environment.
5.1.8 Barrier face coverings with replaceable filters shall have means for reducing the likelihood of improper filter placement in
the product. Where these configurations exist, the manufacturer shall provide specific instructions that address the use and care of
their products relative to filter replacement and disposal of filtering components or cleaning/laundering of reusable parts of the
barrier face covering.
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5.1.9 Barrier face coverings shall be permitted to include transparent materials for the purpose of allowing others to view the
wearer’s lips, but these configurations are still required to meet the performance requirements of Section 6 where the transparent
portions of the barrier face coverings are part of the tested samples.
5.2 Retention System:
5.2.1 Barrier face coverings shall have a means for keeping the barrier face covering over the wearer’s nose and mouth for the
expected period of use and range of activities.
NOTE 14—Examples of retention systems include, but are not limited to: ties, elastic ear loops, and head harnesses. In some cases where the retention
system is integrated with the filtering area, such as tubular neck garments (sometimes referred to as gaiters), the area intended to cover the wearer’s nose
and mouth must be clearly identifiable and proper orientation described in the user instructions. The effectiveness of these systems for keeping the barrier
face covering on the wearer’s head and maintaining coverage of wearer’s nose and mouth varies with the type of retention system in combination with
the materials of construction and the overall design. Subsection 5.4 includes an assessment as a degree for how well the barrier face covering fits on
individuals’ faces. For adult products, the use of plastic toggles or slides is permitted but should not be able to release from the tie or free end (thus leaving
the ability of the mask to fall open).
5.2.2 Where the barrier face covering uses a head harness, the head harness shall provide for adjustment to allow proper fit on
the wearer’s head. When the head harness is made from elastic materials, the elasticity of the harness material is considered
adequate adjustability for proper use.
5.3 Sizing:
5.3.1 Where intended to be worn by a range of individuals, multiple sizes shall be permitted, but not required, to allow a single
model to fit a wide variety of the end user population, excluding very young children (<2 years). Different sizing for children versus
adults is permitted.
5.3.2 Barrier face coverings shall be permitted to be offered in single sizes for the general population and for specific population
groups such as children.
NOTE 15—Anthropometric data for adult populations from the National Institute for Occupational Safety and Health are available as a resource for product
size development. For the date of this specification, there were no known human subject panels for children’s sizes.
5.4 Leakage Assessment:
5.4.1 The leakage assessment shall be reported by the manufacturer as part of the supplier’s declaration of conformity (see Section
12).
5.4.2 As part of its declaration, the manufacturer shall report that the product reduces leakage around the perimeter or other areas
of the barrier face covering based upon an analysis of the product design.
5.4.2.1 The manufacturer is permitted to conduct quantitative testing to supplement its product design analysis self-declaration.
When used, the leakage ratio shall be determined using Test Method F3407, with the modifications specified in 8.3.
5.4.3 Where barrier face coverings are reusable and intended for laundering or cleaning, the product design analysis shall be
applied to barrier face coverings both in a new condition and after the maximum number of laundering or cleaning cycles as
specified by the manufacturer according to the manufacturer’s care instructions.
NOTE 16—Examples of different means to accomplish a leakage assessment includes dimensional analysis or computer modeling where the product design
is electronically captured and then compared to how the product can be placed on computer-generated faces of varying dimensions. An alternative
approach is to physically place barrier face coverings on standardized head or head/torso forms (such as those specified in ISO 16900-5) and judge their
respective areas of coverage and visually observe (or measure) any gaps between the barrier face covering perimeter and underlying face portions of the
head or head-torso form. However, it is important to point out that the absence or existence of visual gaps may not be truly indicative of whether leakage
The report, “A Head-and-Face Anthropometric Survey of U.S. Respirator Users,” is available from Journal of Occupational and Environmental Hygiene, Vol 2, No. 11,
2005, pp. 567–76. DOI: 10.1080/15459620500324727. https://www.nap.edu/resource/11815/Anthrotech_report.pdf. This report provides key facial dimensions for persons
aged 18 to 55. This report may not address the full range of adult facial dimensions for all populations.
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is likely or not. It is also possible to apply this approach to a number of human subjects representing a range of facial dimensions such as those described
in Appendix X1. AATCC M14-2020 is an additional reference for evaluating conformity of the barrier face covering on respective wearers providing
appropriate coverage with gaps that could result in leakage.
5.5 Accessories:
5.5.1 Where accessories are provided that include but are not limited to braces or similar devices that affect the leakage design
analysis and quantitative testing of barrier face coverings, these items shall be explicitly disclosed in the test report and described
as part of the user instructions provided by the product manufacturer as required in Section 11.
6. Performance Requirements
6.1 Barrier face coverings shall meet the requirements specified in Table 1.
6.2 Where the barrier face covering is reusable and intended to be laundered or cleaned, barrier face coverings shall meet each
of the requirements in Table 1, both in a new condition and after the maximum number of laundering or cleaning cycles specified
for the product in accordance with 7.3.
7. Sampling and Conditioning
7.1 Type of Samples—Testing shall be performed on complete barrier face coverings or materials as specified in each individual
test method in Section 8.
7.1.1 Where materials are specified as the samples in the individual test method, these samples shall be taken from complete
barrier face coverings unless the nature of the testing requires larger samples than what can be obtained from any particular finished
product.
7.1.2 Where barrier face coverings include embellishments such as logos, emblems, embossed lines, or other additive features for
appearance purposes, sample selection shall account for the maximum impact of these features on the performance of the product.
NOTE 17—It is recommended that samples be selected that include the largest affected area
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