ASTM F311-08 (2020) PDF

Full title and description

ASTM F311-08(2020) — Standard Practice for Processing Aerospace Liquid Samples for Particulate Contamination Analysis Using Membrane Filters. This practice describes the accepted procedure for preparing and filtering measured volumes of aerospace liquid samples through membrane filters so that particulate contamination can be visually analysed or otherwise quantified using downstream methods.

Designation and current reapproval: F311-08(2020).

Abstract

This brief practice specifies procedures for the filtration and handling of aerospace liquid samples to permit particulate contamination analysis using membrane filters. It covers filtration of measured liquid volumes, handling to minimize particle loss, and is limited by liquid-to-filter compatibility. The practice describes handling of particles across a wide size range (noted in the standard as approximately 2 μm up to 1000 μm in the reapproved 2020 text).

General information

• Status: Active (current edition/reapproval 2020).
• Publication date: Reapproved/issued 2020 (designation F311-08(2020); ASTM record shows updates in April 2020).
• Publisher: ASTM International (formerly American Society for Testing and Materials).
• ICS / categories: Aerospace components/contamination control (ICS example code cited in catalogue listings: 49.035 — components for aerospace construction).
• Edition / version: F311-08 original (2008) — reapproved as F311-08(2020).
• Number of pages: 3 pages (short practice).

Scope

The practice covers processing of liquids in preparation for particulate contamination analysis using membrane filters, including procedures for filtering a measured volume so particles are randomly distributed on the filter surface for subsequent analysis. It is limited by the compatibility of the liquid with the chosen membrane filter and is intended for particle handling with minimal loss. The practice is intended to support visual contamination methods and referenced analysis methods noted in the standard.

Key topics and requirements

• Procedure for filtering a measured volume of liquid through a membrane filter so particulate matter is suitable for analysis.
• Particle handling guidance to minimize losses (standard text cites particle-size handling from about 2 μm up to 1000 μm in the reapproved text).
• Equipment and apparatus: membrane filter support (fritted-glass, sintered-metal, polyphenyl-sulfone or stainless steel screen), vacuum flask, funnel/funnel-holding device, forceps, and clean bench/hood recommendations.
• Notes on calibration (e.g., effective area calibration and funnel volume calibration when used to measure sample volume).
• Compatibility limitation: practice applies only when sample liquids are compatible with the selected membrane filter material.
• Cross-references: intended to be used with related sampling and analysis practices/methods referenced within the standard (see Related standards).

Typical use and users

Used by aerospace contamination-control engineers, materials and test laboratories, quality assurance personnel, spacecraft and component manufacturers, and suppliers who perform particulate contamination monitoring and analysis of fluids (cleaning solvents, rinses, hydraulic fluids, etc.) in aerospace applications. It is typically applied where membrane filtration is the chosen preparatory step prior to visual or instrumental particle analysis.

Related standards

ASTM F311 is intended to be used with companion sampling and analysis documents referenced in its normative references, including Practice F302 and Practices F303 (sampling), Method F312 and Test Method F314 (visual contamination/analysis), and several general ASTM test methods and specifications cited in the practice (examples include D1193 for reagent water and other referenced methods listed in the standard).

Keywords

aerospace; particulate contamination; membrane filter; liquid sample processing; contamination analysis; vacuum filtration; particle sizing; sample preparation; F311-08(2020).

FAQ

Q: What is this standard?

A: ASTM F311-08(2020) is a short ASTM practice that specifies how to process aerospace liquid samples by filtering measured volumes through membrane filters so particulate contamination can be analysed.

Q: What does it cover?

A: It covers the filtration procedure, handling and transfer of particulates to minimize loss, equipment recommendations (filter supports, vacuum apparatus, clean benches), calibration notes, and limitations based on liquid-to-filter compatibility. The reapproved 2020 text clarifies particle-size handling and other procedural details.

Q: Who typically uses it?

A: Aerospace test laboratories, contamination-control engineers, manufacturers and suppliers of aerospace components, and quality assurance staff who need a standard method for preparing liquid samples prior to particulate analysis.

Q: Is it current or superseded?

A: The designation F311-08(2020) indicates the 2008 practice was reapproved in 2020; listings from ASTM show the standard as active/reapproved in 2020. Users should consult the ASTM organization for the absolute current status before formal use.

Q: Is it part of a series?

A: It is part of a family of contamination-control and sampling/analysis practices maintained under ASTM Committee E21 (Space Simulation and Applications of Space Technologies) and subcommittee E21.05 on Contamination; it is intended to be used alongside F302, F303, F312, F314 and other referenced methods.

Q: What are the key keywords?

A: Aerospace, particulate contamination, membrane filters, liquid sampling, filtration, sample preparation, vacuum filtration, contamination analysis.