ASTM F312-08

Standard Test Methods for Microscopical Sizing and Counting Particles from Aerospace Fluids on Membrane Filters

SIGNIFICANCE AND USE
Reported particle size measurement is a function of both the actual particle dimension and shape factor as well as the particular physical or chemical properties of the particle being measured. Caution is required when comparing data from instruments operating on different physical or chemical parameters or with different particle size measurement ranges. Sample acquisition, handling and preparation can also affect the reported particle size results.
SCOPE
1.1 These test methods cover the determination of the size distribution and quantity of particulate matter contamination from aerospace fluids isolated on a membrane filter. The microscopical techniques described may also be applied to other properly prepared samples of small particles. Two test methods are described for sizing particles as follows:
1.1.1 Test Method A—Particle sizes are measured as the diameter of a circle whose area is equal to the projected area of the particle.
1.1.2 Test Method B—Particle sizes are measured by their longest dimension.
1.2 The test methods are intended for application to particle contamination determination of aerospace fluids, gases, surfaces, and environments.
1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.4 These test methods do not provide for sizing particles smaller than 5 μm.
Note 1—Results of these methods are subject to variables inherent in any statistical method. The use of these methods as a standard for initially establishing limits should be avoided unless ample tolerances are permissible.  
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 and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 31-Oct-2008
• Technical Committee: E21 - Space Simulation and Applications of Space Technology
• Drafting Committee: E21.05 - Contamination

Relations

• Replaces: ASTM F312-97(2003) - Standard Test Methods for Microscopical Sizing and Counting Particles from Aerospace Fluids on Membrane Filters
• Effective Date: 01-Nov-2008
• Referred By: ASTM D6224-22 - Standard Practice for In-Service Monitoring of Lubricating Oil for Auxiliary Power Plant Equipment
• Effective Date: 01-Nov-2008
• Referred By: ASTM D4378-22 - Standard Practice for In-Service Monitoring of Mineral Turbine Oils for Steam, Gas, and Combined Cycle Turbines
• Effective Date: 01-Nov-2008
• Referred By: ASTM D6439-23 - Standard Guide for Cleaning, Flushing, and Purification of Steam, Gas, and Hydroelectric Turbine Lubrication Systems
• Effective Date: 01-Nov-2008
• Referred By: ASTM G121-18 - Standard Practice for Preparation of Contaminated Test Coupons for the Evaluation of Cleaning Agents
• Effective Date: 01-Nov-2008
• Referred By: ASTM F331-13(2020) - Standard Test Method for Nonvolatile Residue of Solvent Extract from Aerospace Components (Using Flash Evaporator)
• Effective Date: 01-Nov-2008
• Referred By: ASTM F303-08(2023)e1 - Standard Practices for Sampling for Particles in Aerospace Fluids and Components
• Effective Date: 01-Nov-2008
• Referred By: ASTM D7670-10(2021) - Standard Practice for Processing In-service Fluid Samples for Particulate Contamination Analysis Using Membrane Filters
• Effective Date: 01-Nov-2008
• Referred By: ASTM F311-08(2020) - Standard Practice for Processing Aerospace Liquid Samples for Particulate Contamination Analysis Using Membrane Filters
• Effective Date: 01-Nov-2008
• Referred By: ASTM D4898-16 - Standard Test Method for Insoluble Contamination of Hydraulic Fluids by Gravimetric Analysis
• Effective Date: 01-Nov-2008
• Referred By: ASTM E2090-12(2020) - Standard Test Method for Size-Differentiated Counting of Particles and Fibers Released from Cleanroom Wipers Using Optical and Scanning Electron Microscopy
• Effective Date: 01-Nov-2008
• Referred By: ASTM G93/G93M-19 - Standard Guide for Cleanliness Levels and Cleaning Methods for Materials and Equipment Used in Oxygen-Enriched Environments
• Effective Date: 01-Nov-2008
• Referred By: ASTM E2088-06(2021) - Standard Practice for Selecting, Preparing, Exposing, and Analyzing Witness Surfaces for Measuring Particle Deposition in Cleanrooms and Associated Controlled Environments
• Effective Date: 01-Nov-2008
• Referred By: ASTM E1216-21 - Standard Practice for Sampling for Particulate Contamination by Tape Lift
• Effective Date: 01-Nov-2008
• Referred By: ASTM D4174-23 - Standard Practice for Cleaning, Flushing, and Purification of Petroleum Fluid Hydraulic Systems
• Effective Date: 01-Nov-2008

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: F312 − 08
StandardTest Methods for
Microscopical Sizing and Counting Particles from
1
Aerospace Fluids on Membrane Filters
ThisstandardisissuedunderthefixeddesignationF312;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginal
adoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscript
epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope F302Practice for Field Sampling of Aerospace Fluids in
Containers
1.1 These test methods cover the determination of the size
F303Practices for Sampling for Particles in Aerospace
distribution and quantity of particulate matter contamination
Fluids and Components
from aerospace fluids isolated on a membrane filter. The
F311Practice for ProcessingAerospace Liquid Samples for
microscopical techniques described may also be applied to
Particulate ContaminationAnalysis Using Membrane Fil-
other properly prepared samples of small particles. Two test
ters
methods are described for sizing particles as follows:
F314Methods of Test for Identification of Metallic and
1.1.1 Test Method A—Particle sizes are measured as the
Fibrous Contaminants in Aerospace Fluids (Withdrawn
diameterofacirclewhoseareaisequaltotheprojectedareaof
3
1990)
the particle.
F318Practice for Sampling Airborne Particulate Contami-
1.1.2 Test Method B—Particle sizes are measured by their
nation in Cleanrooms for Handling Aerospace Fluids
longest dimension.
1.2 The test methods are intended for application to particle 3. Terminology
contamination determination of aerospace fluids, gases,
3.1 Definitions:
surfaces, and environments.
3.1.1 unit area—the area selected for counting particles.
1.3 The values stated in SI units are to be regarded as This may be the area of a reticle grid or some subdivision
standard. No other units of measurement are included in this thereof, the area of one imprinted membrane grid, or any other
standard. accurately calibrated area.
3.1.2 effective filter area—the area of the membrane which
1.4 These test methods do not provide for sizing particles
entraps the particles to be counted.
smaller than 5 µm.
3.1.3 particle size—the size of a particle as defined by area
NOTE 1—Results of these methods are subject to variables inherent in
comparison or by its longest dimension.
anystatisticalmethod.Theuseofthesemethodsasastandardforinitially
establishing limits should be avoided unless ample tolerances are permis-
sible. 4. Summary of Test Methods
1.5 This standard does not purport to address all of the
4.1 The membrane is examined through a microscope and
safety concerns, if any, associated with its use. It is the
the particles counted according to size or size categories using
responsibility of the user of this standard to establish appro-
a calibrated reticle. The total number of particles present is
priate safety and health practices and determine the applica-
estimated by statistical methods from the actual number of
bility of regulatory limitations prior to use.
particles counted. Either sizing Test Method A or B may be
selected according to the preference and results expected.
2. Referenced Documents
2
5. Significance and Use
2.1 ASTM Standards:
5.1 Reportedparticlesizemeasurementisafunctionofboth
1 the actual particle dimension and shape factor as well as the
These test methods are under the jurisdiction of ASTM Committee E21 on
Space Simulation and Applications of Space Technology and are the direct
particular physical or chemical properties of the particle being
responsibility of Subcommittee E21.05 on Contamination
measured. Caution is required when comparing data from
Current edition approved Nov. 1, 2008. Published December 2008. Originally
instrumentsoperatingondifferentphysicalorchemicalparam-
approvedin1969.Lastpreviouseditionapprovedin2003asF312–97(2003).DOI:
eters or with different particle size measurement ranges.
10.1520/F0312-08.
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
3
Standards volume information, refer to the standard’s Document Summary page on The last approved version of this historical standard is referenced on
the ASTM website. www.astm.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
F312 − 08
Sample acquisition, handling and preparation can also affect rulings on the stage micrometer. Detailed calibration proce-
the reported particle size results. dures and a discussion of errors are given in Appendix X1.
8.2 The area extrapolation factor used for statistical count-
6. Apparatus
ing is determined by the ratio of the area counted to the total
6.1 Microscope,
...

This document is not anASTM standard and is intended only to provide the user of anASTM 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:F312–97 (Reapproved 2003) Designation:F312–08
Standard Test Methods for
Microscopical Sizing and Counting Particles from
1
Aerospace Fluids on Membrane Filters
This standard is issued under the fixed designation F 312; 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 These test methods cover the determination of the size distribution and quantity of particulate matter contamination from
aerospace fluids isolated on a membrane filter. The microscopical techniques described may also be applied to other properly
prepared samples of small particles. Two test methods are described for sizing particles as follows:
1.1.1 Test Method A—Particle sizes are measured as the diameter of a circle whose area is equal to the projected area of the
particle.
1.1.2 Test Method B—Particle sizes are measured by their longest dimension.
1.2 The test methods are intended for application to particle contamination determination of aerospace fluids, gases, surfaces,
and environments.
1.3These test methods do not provide for sizing particles smaller than 5 µm.
1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.4 These test methods do not provide for sizing particles smaller than 5 µm.
NOTE 1—Results of these methods are subject to variables inherent in any statistical method. The use of these methods as a standard for initially
establishing limits should be avoided unless ample tolerances are permissible.
1.4
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 and health practices and determine the applicability of regulatory
limitations prior to use.
2. Referenced Documents
2
2.1 ASTM Standards:
F 302 Practice for Field Sampling of Aerospace Fluids in Containers
2
F 303Practices for SamplingAerospace Fluids from Components Practices for Sampling for Particles inAerospace Fluids and
Components
F 311 Practice for Processing Aerospace Liquid Samples for Particulate Contamination Analysis Using Membrane Filters
3
F 314Test Method of Test for Identification of Metallic and Fibrous Contaminants in Aerospace Fluids
F 318 Practice for Sampling Airborne Particulate Contamination in Clean Rrooms for Handling Aerospace Fluids
3. Terminology
3.1 Definitions:
3.1.1 unit area—the area selected for counting particles. This may be the area of a reticle grid or some subdivision thereof, the
area of one imprinted membrane grid, or any other accurately calibrated area.
3.1.2 effective filter area—the area of the membrane which entraps the particles to be counted.
3.1.3 particle size—the size of a particle as defined by area comparison or by its longest dimension.
1
These test methods are under the jurisdiction of ASTM Committee E21 on Space Simulation and Application of Space Technologies are the direct responsibility of
Subcommittee E21.05 on Contamination.
Current edition approved April 10, 1997. Published November 1997. Originally published as F312–69. Last previous edition F312–96.
1
These test methods are under the jurisdiction of ASTM Committee E21 on Space Simulation and Applications of Space Technology are the direct responsibility of
Subcommittee E21.05 on Contamination
Current edition approved Nov. 1, 2008. Published December 2008. Originally approved in 1969. Last previous edition approved in 2003 as F 312 – 97(2003).
2
For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
, Vol 10.05.volume information, refer to the standard’s Document Summary page on the ASTM website.
3
Annual Book of ASTM Standards, Vol 14.02.
3
Withdrawn. The last approved version of this historical standard is referenced on www.astm.org.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
1

---------------------- Page: 1 ----------------------
F312–08
4. Summary of Test Methods
4.1 The membrane is examined through a microscope and the particles counted according to size or size categories using a
calibrated reticle. The total number of particles present is estimated by statistical methods fr
...