ASTM F25/F25M-09(2015)

Standard Test Method for Sizing and Counting Airborne Particulate Contamination in Cleanrooms and Other Dust-Controlled Areas

ABSTRACT
This test method covers the apparatuses required, sampling methods, standard procedures and calculations, and test reports for counting and sizing airborne microparticulate matter, the sampling areas for which are specifically those with contamination levels typical of cleanrooms and dust-controlled areas. The test method is based on the microscopical examination of particles impinged upon a membrane filter with the aid of a vacuum. Sampling may be done in a cleanroom, clean zone, or other controlle areas, or in a duct or pipe, wherein the number of sampling points is proportional to the floor area of the enclosure to be checked. The apparatus and facilities required are typical of a laboratory for the study of macroparticle contamination. The operator must have adequate basic training in microscopy and the techniques of particle sizing and counting.
SCOPE
1.1 This test method covers counting and sizing airborne particulate matter 5 µm and larger (macroparticles). The sampling areas are specifically those with contamination levels typical of cleanrooms and dust-controlled areas.  
1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.  
1.3 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 and health practices and determine the applicability of regulatory requirements prior to use.

General Information

• Status: Historical
• Publication Date: 30-Sep-2015
• ICS: 13.040.30 - Workplace atmospheres
• Technical Committee: E21 - Space Simulation and Applications of Space Technology
• Drafting Committee: E21.05 - Contamination

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: F25/F25M − 09 (Reapproved 2015)
Standard Test Method for
Sizing and Counting Airborne Particulate Contamination in
1
Cleanrooms and Other Dust-Controlled Areas
This standard is issued under the fixed designation F25/F25M; 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 2.3 IEST Document:
IEST-G-CC1003Measurement of Airborne Macroparticles
1.1 This test method covers counting and sizing airborne
4
(1999)
particulate matter 5 µm and larger (macroparticles). The
2.4 SAE Document:
samplingareasarespecificallythosewithcontaminationlevels
SAEAbstractARP-743, Procedure for the Determination of
typical of cleanrooms and dust-controlled areas.
Particulate Contamination of Air in Dust-Controlled
1.2 The values stated in either SI units or inch-pound units
5
Spaces by Particle Count Method, August 1962
are to be regarded separately as standard. The values stated in
each system may not be exact equivalents; therefore, each
3. Terminology
system shall be used independently of the other. Combining
3.1 Definitions:
values from the two systems may result in non-conformance
3.1.1 airflow:
with the standard.
3.1.1.1 unidirectional airflow—airflowwhichhasasingular
1.3 This standard does not purport to address all of the
direction of flow and may or may not contain uniform
safety concerns, if any, associated with its use. It is the
velocities of air flow along parallel lines.
responsibility of the user of this standard to establish appro-
NOTE 1—Formerly known as laminar airflow.
priate safety and health practices and determine the applica-
3.1.1.2 non-unidirectional airflow—air distribution where
bility of regulatory requirements prior to use.
the supply air entering the room mixes with the internal air by
2. Referenced Documents
means of induction.
2
2.1 ASTM Standards:
3.1.2 critical pressure—for an orifice, with a constant up-
F50Practice for Continuous Sizing and Counting of Air-
stream pressure, the downstream pressure at which the flow
borne Particles in Dust-Controlled Areas and Clean
will not increase when the downstream pressure decreases.
Rooms Using Instruments Capable of Detecting Single
3.1.3 critical pressure ratio—the ratio of the critical pres-
Sub-Micrometre and Larger Particles
sure of an orifice to the entrance pressure.
2.2 ISO Standard:
3.1.4 customer—organization, or the agent thereof, respon-
ISO 14644-1 Cleanrooms and Associated Controlled
3 sible for specifying the requirements of a cleanroom or clean
Environments—Part 1: Classification of Air Cleanliness
zone.
3.1.5 fiber—particlehavinganaspect(length-to-width)ratio
1
This test method is under the jurisdiction of ASTM Committee E21 on Space
of 10 or more.
Simulation andApplications of SpaceTechnology and is the direct responsibility of
Subcommittee E21.05 on Contamination.
3.1.6 macroparticle—particle with an equivalent diameter
Current edition approved Oct. 1, 2015. Published November 2015. Originally
greater than 5 µm.
approved in 1963. Last previous edition approved in 2009 as F25–09. DOI:
10.1520/F0025_F0025M-09R15.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
4
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Available from Institute of Environmental Sciences and Technology (IEST),
Standards volume information, refer to the standard’s Document Summary page on Arlington Place One, 2340 S.Arlington Heights Rd., Suite 100,Arlington Heights,
the ASTM website. IL 60005-4516, http://www.iest.org.
3 5
Available fromAmerican National Standards Institute (ANSI), 25 W. 43rd St., Available from Society of Automotive Engineers (SAE), 400 Commonwealth
4th Floor, New York, NY 10036, http://www.ansi.org. Dr., Warrendale, PA 15096-0001, http://www.sae.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

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F25/F25M − 09 (2015)
FIG. 2 Typical Air Sampling-Filtration Apparatus
5. Apparatus
6
5.1 Filter Holder, aerosol open type having an effective
FIG. 1 Suitable Microscope: Inclined Binocular Body; Mechanical
2
filtering area of 960 6 25 mm .
Stage; Triple Nosepiece; Ocular-Objective Combination to Obtain
40 to 45× and 90 to 150× Magnification 7
5.2 Adapter.
8
5.3 Flow-Limiting Orifice, 10 L/min.
3.1.7 M descriptor—measured or specified concentration of
9
5.4 Membrane Filters, black, 0.80-µm mean pore size,
macroparticlespercubicmetreofair,expressedintermsofthe
47-mmdiameter,withimprintedgridsquareshavingsides3.10
equivalent diameter that is characteristic of the measurement
...

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: F25/F25M − 09 F25/F25M − 09 (Reapproved 2015)
Standard Test Method for
Sizing and Counting Airborne Particulate Contamination in
1
Cleanrooms and Other Dust-Controlled Areas
This standard is issued under the fixed designation F25/F25M; 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.
1. Scope
1.1 This test method covers counting and sizing airborne particulate matter 5 μm and larger (macroparticles). The sampling
areas are specifically those with contamination levels typical of cleanrooms and dust-controlled areas.
1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each
system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the
two systems may result in non-conformance with the standard.
1.3 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 and health practices and determine the applicability of regulatory
requirements prior to use.
2. Referenced Documents
2
2.1 ASTM Standards:
F50 Practice for Continuous Sizing and Counting of Airborne Particles in Dust-Controlled Areas and Clean Rooms Using
Instruments Capable of Detecting Single Sub-Micrometre and Larger Particles
2.2 ISO Standard:
3
ISO 14644-1 Cleanrooms and Associated Controlled Environments—Part 1: Classification of Air Cleanliness
2.3 IEST Document:
4
IEST-G-CC1003 Measurement of Airborne Macroparticles (1999)
2.4 SAE Document:
SAE Abstract ARP-743, Procedure for the Determination of Particulate Contamination of Air in Dust-Controlled Spaces by
5
Particle Count Method, August 1962
3. Terminology
3.1 Definitions:
3.1.1 airflow:
3.1.1.1 unidirectional airflow—air flow which has a singular direction of flow and may or may not contain uniform velocities
of air flow along parallel lines.
NOTE 1—Formerly known as laminar airflow.
3.1.1.2 non-unidirectional airflow—air distribution where the supply air entering the room mixes with the internal air by means
of induction.
3.1.2 critical pressure—for an orifice, with a constant upstream pressure, the downstream pressure at which the flow will not
increase when the downstream pressure decreases.
1
This test method is under the jurisdiction of ASTM Committee E21 on Space Simulation and Applications of Space Technology and is the direct responsibility of
Subcommittee E21.05 on Contamination.
Current edition approved April 1, 2009Oct. 1, 2015. Published April 2009November 2015. Originally approved in 1963. Last previous edition approved in 20042009 as
F25 – 04.F25 – 09. DOI: 10.1520/F0025_F0025M-09.10.1520/F0025_F0025M-09R15.
2
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.
3
Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http://www.ansi.org.
4
Available from Institute of Environmental Sciences and Technology (IEST), Arlington Place One, 2340 S. Arlington Heights Rd., Suite 100, Arlington Heights, IL
60005-4516, http://www.iest.org.
5
Available from Society of Automotive Engineers (SAE), 400 Commonwealth Dr., Warrendale, PA 15096-0001, http://www.sae.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
F25/F25M − 09 (2015)
3.1.3 critical pressure ratio—the ratio of the critical pressure of an orifice to the entrance pressure.
3.1.4 customer—organization, or the agent thereof, responsible for specifying the requirements of a cleanroom or clean zone.
3.1.5 fiber—particle having an aspect (length-to-width) ratio of 10 or more.
3.1.6 macroparticle—particle with an equivalent diameter greater than 5 μm.
3.1.7 M descriptor—measured or specified concentration of macroparticles per cubic metre of air, expressed in terms of the
equivalent diameter that is characteristic of the measurement method used.
3.1.7.1 Discussion—
The M descriptor may be regarded as an upper limit for the averages
...