ASTM E1115-11(2017)

Standard Test Method for Evaluation of Surgical Hand Scrub Formulations

SIGNIFICANCE AND USE
5.1 The procedure in this test method should be used to evaluate the activity of the test formulation in reducing the bacterial population of the hands immediately after a single use and to determine persistent activity (inhibition of growth) after 6 h. Optionally, measurements of persistent activity after a 3 h period and measurements of cumulative activity may be made after repetitive uses over a five day period.
SCOPE
1.1 This test method is designed to measure the reduction of microbial flora on the skin. It is intended for determining both immediate and persistent (continuing antimicrobial effect) microbial reductions, after single or repetitive treatments, or both. It may also be used to measure cumulative antimicrobial activity after repetitive treatments.  
1.2 A knowledge of microbiological techniques is required for these procedures.  
1.3 Performance of this procedure requires the knowledge of regulations pertaining to the protection of human subjects (21 CFR, Parts 50 and 56)  
1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.4.1 In this test method, SI units are used for all applications, except for distance, in which case inches are used and SI units follow in parentheses.  
1.5 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.  
1.6 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.

General Information

• Status: Published
• Publication Date: 31-Oct-2017
• ICS: 11.080.20 - Disinfectants and antiseptics
• ICS: 71.100.35 - Chemicals for industrial and domestic disinfection purposes
• Technical Committee: E35 - Pesticides, Antimicrobials, and Alternative Control Agents
• Drafting Committee: E35.15 - Antimicrobial Agents

Relations

• Replaces: ASTM E1115-11 - Standard Test Method for Evaluation of Surgical Hand Scrub Formulations
• Effective Date: 01-Nov-2017
• Refers: ASTM E2180-24 - Standard Test Method for Determining the Activity of Incorporated Antimicrobial Agent(s) In Polymeric or Hydrophobic Materials
• Effective Date: 01-Apr-2024
• Refers: ASTM E2180-18 - Standard Test Method for Determining the Activity of Incorporated Antimicrobial Agent(s) In Polymeric or Hydrophobic Materials
• Effective Date: 01-May-2018
• Refers: ASTM E2180-07(2017) - Standard Test Method for Determining the Activity of Incorporated Antimicrobial Agent(s) In Polymeric or Hydrophobic Materials
• Effective Date: 01-Apr-2017
• Refers: ASTM E2180-07(2012) - Standard Test Method for Determining the Activity of Incorporated Antimicrobial Agent(s) In Polymeric or Hydrophobic Materials
• Effective Date: 01-Apr-2012
• Refers: ASTM E1054-08 - Standard Test Methods for Evaluation of Inactivators of Antimicrobial Agents
• Effective Date: 01-Apr-2008
• Refers: ASTM E2180-07 - Standard Test Method for Determining the Activity of Incorporated Antimicrobial Agent(s) In Polymeric or Hydrophobic Materials
• Effective Date: 01-Nov-2007
• Refers: ASTM D1193-06 - Standard Specification for Reagent Water
• Effective Date: 01-Mar-2006
• Refers: ASTM E1054-02 - Standard Test Methods for Evaluation of Inactivators of Antimicrobial Agents
• Effective Date: 10-May-2002
• Refers: ASTM E2180-01 - Standard Test Method for Determining the Activity of Incorporated Antimicrobial Agent(s) In Polymeric or Hydrophobic Materials
• Effective Date: 10-Dec-2001
• Refers: ASTM D1193-99e1 - Standard Specification for Reagent Water
• Effective Date: 10-Feb-1999
• Refers: ASTM D1193-99 - Standard Specification for Reagent Water
• Effective Date: 10-Feb-1999
• Referred By: ASTM E2613-23 - Standard Practice for Determining the Fungus-Eliminating Effectiveness of Hygienic Handwash and Handrub Agents Using the Fingerpads of Adults
• Effective Date: 01-Nov-2017
• Referred By: ASTM E1054-22 - Standard Practices for Evaluation of Inactivators of Antimicrobial Agents
• Effective Date: 01-Nov-2017
• Referred By: ASTM E2276-10(2019) - Standard Test Method for Determining the Bacteria-Eliminating Effectiveness of Hygienic Handwash and Handrub Agents Using the Fingerpads of Adults
• Effective Date: 01-Nov-2017

Overview

ASTM E1115-11(2017): Standard Test Method for Evaluation of Surgical Hand Scrub Formulations is an internationally recognized standard from ASTM International. This standard establishes test methods for measuring the effectiveness of surgical hand scrub formulations in reducing bacterial populations on the skin. The method determines both immediate and persistent antimicrobial effects from a single or repeated application and can also measure cumulative antimicrobial activity after repetitive uses.

The procedure is widely referenced in healthcare, microbiological product evaluation, and regulatory compliance. It aligns with global standardization principles and is developed with references to FDA regulations for human subject protection (21 CFR Parts 50 and 56).

Key Topics

• Immediate and Persistent Activity: The test method quantifies the reduction in hand bacterial flora and evaluates how long the antimicrobial effect lasts, up to 6 hours post-treatment. Optionally, activity at 3 hours and cumulative effects from repeated use over five days can be assessed.
• Microbiological Techniques: Requires personnel trained in microbiology and familiarity with colony counting, sampling fluids, and aseptic techniques.
• Standardized Evaluation: Enables the quantitative and statistical assessment of hand scrub efficacy, allowing reliable comparison of formulations.
• Human Subject Safety: Emphasizes adherence to safety, health, and ethical standards, particularly those protecting human research subjects.
• Control of Variables: Considers baseline hand flora, use of appropriate controls, and randomization to reduce bias.
• Regulatory Relevance: Provides data required by regulatory authorities for the evaluation and registration of hand antiseptic products.

Applications

ASTM E1115-11(2017) is practical and widely used in several contexts:

• Healthcare & Surgical Settings: Hospitals and surgical centers use this method to evaluate hand scrubs intended for infection control before invasive procedures. It verifies that hand hygiene products comply with strict clinical standards.
• Product Development & Claims Substantiation: Manufacturers of surgical hand scrubs or antimicrobial handwashes utilize this test method to demonstrate the efficacy of new formulations and to support antimicrobial label claims.
• Regulatory Submissions: Testing results according to ASTM E1115-11(2017) are often required for regulatory filings with agencies like the FDA or equivalent authorities worldwide.
• Quality Control: Laboratories and quality assurance teams use the standard to verify batch consistency and ongoing efficacy after process or ingredient changes.

Related Standards

Several related standards and methods are referenced within and complement ASTM E1115-11(2017):

• ASTM E1054 – Evaluation of inactivators of antimicrobial agents
• ASTM E2180 – Activity of incorporated antimicrobial agent(s) in polymeric or hydrophobic materials
• AATCC 147 – Antibacterial assessment of textile materials (Parallel Streak Method)
• JIS Z 2801 – Test for antimicrobial activity and efficacy (Japan)
• USP <61> – United States Pharmacopeia, Microbial limits test
• 21 CFR Parts 50 and 56 – FDA regulations for human subject protection

Practical Value

• Evidence-Based Product Validation: Ensures that only highly effective surgical hand scrub products are used in critical healthcare contexts.
• Standardization and Repeatability: Supports globally consistent, reproducible testing and evaluation criteria for antimicrobial products.
• Patient and Personnel Safety: Minimizes infection risks in healthcare environments by validating the effectiveness of surgical hand hygiene products.
• Regulatory Compliance: Provides a trusted foundation for meeting international regulatory and market-entry requirements for antimicrobial hand hygiene products.

Adhering to ASTM E1115-11(2017) ensures that evaluation of surgical hand scrub formulations is accurate, reliable, and meaningful, supporting both industry best practices and public health outcomes.

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: E1115 − 11 (Reapproved 2017)
Standard Test Method for
Evaluation of Surgical Hand Scrub Formulations
This standard is issued under the fixed designation E1115; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope E1054Test Methods for Evaluation of Inactivators of Anti-
microbial Agents
1.1 Thistestmethodisdesignedtomeasurethereductionof
E2180Test Method for Determining the Activity of Incor-
microbial flora on the skin. It is intended for determining both
porated Antimicrobial Agent(s) In Polymeric or Hydro-
immediate and persistent (continuing antimicrobial effect)
phobic Materials
microbial reductions, after single or repetitive treatments, or
2.2 Other Documents:
both. It may also be used to measure cumulative antimicrobial
21 CFRParts 50 and 56
activity after repetitive treatments.
AATCC 147–2004Antibacterial Assessment of Textile Ma-
1.2 A knowledge of microbiological techniques is required
terials: Parallel Streak Method
for these procedures.
JIS Z 2801:2000,Antimicrobial Products—Test forAntimi-
1.3 Performance of this procedure requires the knowledge
crobial Activity and Efficacy
of regulations pertaining to the protection of human subjects
USP32United States Pharmacopeia, Chapter 61 “Microbial
(21 CFR, Parts 50 and 56)
Limits Test”, 2009
1.4 The values stated in SI units are to be regarded as
3. Terminology
standard. No other units of measurement are included in this
3.1 Definitions:
standard.
1.4.1 In this test method, SI units are used for all 3.1.1 active ingredient—a substance added to a formulation
specifically for the inhibition or inactivation of microorgan-
applications,exceptfordistance,inwhichcaseinchesareused
and SI units follow in parentheses. isms.
3.1.2 cleansing wash—a non-antimicrobial wash intended
1.5 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the to remove gross soil or residues from the hands.
responsibility of the user of this standard to establish appro-
3.1.3 cleansing wash formulation—a liquid castile soap or
priate safety, health, and environmental practices and deter-
other liquid soap with neutral pH which does not contain an
mine the applicability of regulatory limitations prior to use.
antimicrobial.
1.6 This international standard was developed in accor-
3.1.4 cumulative effect—a progressive decrease in the num-
dance with internationally recognized principles on standard-
ber of microorganisms recovered following repeated applica-
ization established in the Decision on Principles for the
tions.
Development of International Standards, Guides and Recom-
3.1.5 internal reference formulation—a formulation with
mendations issued by the World Trade Organization Technical
demonstrated performance characteristics within the labora-
Barriers to Trade (TBT) Committee.
tory.
2. Referenced Documents
3.1.6 neutralization—a process that results in quenching or
inactivationoftheantimicrobialactivityofaformulation.This
2.1 ASTM Standards:
D1193Specification for Reagent Water
Available from U.S. Government Printing Office, 732 N. Capitol St.,
This test method is under the jurisdiction of ASTM Committee E35 on Washington, DC 20401, U.S. Government Bookstore, http://bookstore.gpo.gov/
Pesticides, Antimicrobials, and Alternative Control Agents and is the direct baskets/cfr-listing.jsp.
responsibility of Subcommittee E35.15 on Antimicrobial Agents. Technical Manual of the American Association of Textile Chemists and
Current edition approved Nov. 1, 2017. Published December 2017. Originally Colorists (AATCC), 2009, Vol 82, P.O. Box 12215, Research Triangle Park, NC
approved in 1986. Last previous edition approved in 2011 as E1115–11. DOI: 27709, http://www.aatcc.org.
10.1520/E1115-11R17. Available from Japanese Industrial Standards Committee, Divisional Council
For referenced ASTM standards, visit the ASTM website, www.astm.org, or on Consumer Life, Japanese StandardsAssociation (JSA), 4-1-24Akasaka Minato-
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Ku, Tokyo, 107-8440, Japan, http://www.jsa.or.jp.
Standards volume information, refer to the standard’s Document Summary page on AvailablefromU.S.Pharmacopeia(USP),12601TwinbrookPkwy.,Rockville,
the ASTM website. MD 20852-1790, http://www.usp.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
E1115 − 11 (2017)
maybeachievedthroughdilutionoftheformulationorthrough 6.3 Sterilizer—Any suitable steam sterilizer capable of pro-
the use of chemical agents called neutralizers. ducing the conditions of sterilization.
3.1.7 persistence—prolonged or extended antimicrobial ac- 6.4 Timer (stop-clock)—one that displays minutes and sec-
tivity that prevents or inhibits the proliferation or survival of onds.
microorganisms after treatment.
6.5 Hand Washing Sink—Asink of sufficient size to permit
3.1.8 sampling fluid—a buffered solution that aids in recov-
subjects to wash without touching hands to sink surface or
ery of microorganisms from the skin and neutralization of the other subjects.
active ingredient in test and internal reference formulations.
6.5.1 Water Faucet(s)—To be located above the sink at a
heightthatpermitsthehandstobeheldhigherthantheelbows
3.1.9 test formulation—a formulation containing an active
during the washing procedure. (It is desirable for the height of
ingredient(s).
the faucet(s) to be adjustable.)
4. Summary of Test Method
6.6 Tap Water Temperature Regulator and Temperature
Monitor—To monitor and regulate water temperature to 40 6
4.1 This test method is conducted on individuals selected
2°C.
from a group of subjects who have refrained from using any
antimicrobials for at least one week prior to initiation of the
7. Reagents and Materials
test. Subjects are selected from this group on the basis of high
7.1 Petri Dishes—100 by 15 mm. Required for performing
initial bacterial count, ≥1×10 CFU/per hand as determined
Standard Plate Count.
by baseline measurements of the bacteria on their hands using
NOTE 2—Pre-sterilized/disposable plastic petri dishes are available
the recovery techniques in this method.
from most local laboratory supply houses.
4.2 Theselectedsubjectsperformasimulatedsurgicalscrub
7.2 Bacteriological Pipets—10.0 and 2.2 or 1.1-mL capac-
under the supervision of an individual competent in aseptic
ity.
technique. One hand of each subject is sampled immediately
NOTE 3—Pre-sterilized/disposable bacteriological pipets are available
after the scrub (within 1 min), and the other hand, 6 h after
from most local laboratory supply houses.
scrubbing.Onlyonehandofasubjectissampledataspecified
7.3 Water-Dilution Bottles—Any sterilizable container hav-
time. Optionally, another sampling time, 3 h for example, can
ing a 150 to 200-mL capacity and tight closures may be used.
beaddedbetweentheimmediateand6hsamplingtimes.Ifthis
NOTE 4—Dilution bottles of 160-mL capacity having a screw-cap
is desired, the panel size must be increased by 50% to obtain
closure are available from most local laboratory supply houses.
the same number of data points at each designated sampling
7.4 Cleansing Wash Formulation—A mild, non-
interval. Also, a sampling time randomization must be gener-
antimicrobial soft soap such as the following or any other
ated such that one-third of the hands are sampled at each
liquid soap with neutral pH which does not contain an
sampling interval with only one hand of a subject being
antimicrobial:
sampled at a sampling time interval.
Soft soap, 200 g/L
NOTE 1—Data for submission to some regulatory bodies may require
the addition of a positive and negative control in addition to the test
Linseed oil 50 parts by weight
product. For the negative control, 0.9% saline can be used when testing
Potassium hydroxide 9.5 parts
alcohol products and the product vehicle can be used as the negative Ethanol 7 parts
Distilled or high purity water as needed
control when testing non-alcoholic products.
7.4.1 Add linseed oil to a solution of potassium hydroxide
4.3 If demonstration of cumulative activity is desired,
in 15 parts water and heat up to approximately 70°C while
eleven additional scrubs are performed over a 5-day period,
constantlystirring.Addtheethanolandcontinueheatingwhile
one additional time on Day 1, three times on Days 2, 3, and 4
stirring until the saponification process is completed and a
and once on Day 5. The hands are sampled again after the last
sampledissolvesclearlyinwaterandalmostclearlyinalcohol.
scheduled scrub.
The weight of the soft soap is then brought up to 100 parts by
addition of hot water. Take 200 g of the soft soap in 1 L of
5. Significance and Use
water. Dispense in to appropriate containers and sterilize in an
5.1 The procedure in this test method should be used to
autoclave.
evaluate the activity of the test formulation in reducing the
7.5 Gloves for Sampling—Loose-fitting, unlined, powder-
bacterialpopulationofthehandsimmediatelyafterasingleuse
freelatexgloveswhichpossessnoantimicrobialproperties, or
andtodeterminepersistentactivity(inhibitionofgrowth)after
equivalent.
6 h. Optionally, measurements of persistent activity after a 3 h
NOTE 5—A zone of inhibition test such as AATCC 147–2004, Test
period and measurements of cumulative activity may be made
Method E2180, or Japanese Standard JIS Z 2801 may be used to evaluate
after repetitive uses over a five day period.
The sole source of supply of the apparatus (Ansell #579500, sterile, Encore
6. Apparatus
Acclaim Latex Surgical Gloves) known to the committee at this time is PSS
6.1 Colony Counter—Use any of several types.
Medical, Inc. (Cat #105613). If you are aware of alternative suppliers, please
provide this information toASTM International Headquarters.Your comments will
6.2 Incubator—Any incubator capable of maintaining a
receive careful consideration at a meeting of the responsible technical committee,
temperature of 30 6 2°C. which you may attend.
E1115 − 11 (2017)
antimicrobial properties of gloves.
9. Procedure
7.6 Test Formulation—Directions for use of active test
9.1 After subjects have refrained from using antimicrobials
formulationshouldbeutilizedifavailable.Ifnotavailable,use
for at least one week, perform wash with cleansing wash
directions provided in this test method (see 11.1.3).
formulation (see 7.4) using methodology outlined in 10.1 –
10.4. Subjects are not to have washed their hands on this day
7.7 Water—Sterile deionized water or equivalent (Specifi-
2 h prior to baseline determination. After washing, determine
cation D1193, Type III).
first estimate of baseline bacterial population by sampling
7.8 Sampling Fluid —Dissolve 0.4 g KH PO , 10.1 g
2 4
hands and enumerating the bacteria in the sampling fluid.This
Na HPO , 1.0 g isooctylphenoxypolyethoxyethanol (for
2 4
is Day 1 of “Baseline Period.” Repeat this baseline determi-
example, Triton X-100), and appropriately validated neutraliz-
nationprocedureonDays3and7,Days3and5,orDays5and
ers in 1 Ldistilled water.Adjust pH to 7.8 6 1 with 0.1 N HCl
7 of “Baseline Period” to obtain three estimates of baseline
or 01. N NaOH. Dispense to achieve a final volume of 75 6 1
population.Afterobtainingthefirstandsecondestimatesofthe
mL and sterilize.
baseline populations, select subjects who exhibited at each
7.9 Dilution Fluid—Sterile Butterfield’s buffer or other
samplingtimecounts≥1×10 perhand.Thethreeestimatesof
suitable diluent adjusted to pH 7.2 6 0.1 with effective
the baseline population obtained for each of the selected
neutralizer for the test material. Adjust pH with 0.1 N HCl or
subjects are averaged to obtain the mean baseline counts.
0.1 N NaOH. See Test Methods E1054.
9.2 Abasicrandombacterialrecoverysamplingplanshould
7.10 Agar—Soybean-casein Digest agar (USP 32) or other
be followed. The number of subjects and sampling times
solid media appropriately validated to support growth of the
dependonthetestformulationbutmustestablishtheonsetand
test organism with appropriate neutralizers if needed.
extentofthebacterialsuppressionandthedurationofsuppres-
NOTE 6—Inadequate neutralization may result in false interpretation of
sion below the baseline counts. Equal numbers of subjects
the test data. The use of excess chemical neutralizers may exert a toxic
should be assigned per sampling time, test formulation and
effect on the recovery of bacterial cells. The goal, therefore, is to stop
hand.Atypicalbalancedrandomizationplanfortestingablock
antimicrobial activity as early as possible in the sampling/plating process.
If it can be demonstrated that antimicrobial activity is quenched or
ofsixsubjectsfollowswithsamplingat0h,3h(optional),and
inactivated in the sampling fluid then, to reduce the chance of possible
6h.
toxic effects, inactivators should not be added to the dilution fluid or
Subject No. Post Scrub Sampling Time, h
plating media.
0-h 3-h 6-h
7.11 Scrub Sponge and Nail Cleaner Stick—Such as E-Z 1 left hand right hand
2 left hand right hand
Scrub 160 or any equivalent may be used.
3 right hand left hand
4 right hand left hand
8. Subjects
5 left hand right hand
6 right hand left hand
8.1 Recruit a sufficient number (see X1.1) of healthy sub-
jects who have no clinical evidence of dermatoses, open If only 0 h and 6 h post scrub samples are collected the 0 h
will be randomized to the right or left hand.
wounds, or other skin disorders. Exclude any individual
receiving antibiotic therapy and any individual sensitive to
9.2.1 The number of subjects per block ma
...