This practice provides a standard approach to measuring particle deposition, or fallout, in cleanrooms and other controlled environments. It is based on the use of a witness surface to collect particles that deposit from the surrounding environment and subsequently sizing and counting the particles by conventional methods. Several options are introduced, with limitations and guidelines for selecting the best choice for the intended application.

This practice is applicable across numerous industries including aerospace, microelectronics, and pharmaceuticals.

1. Scope

1.1 This practice is intended to assist in the selection, preparation, exposure, and analysis of witness surfaces for the purpose of characterizing particle deposition rates in cleanrooms and associated controlled environments, particularly for aerospace applications.

1.2 Requirements may be defined in terms of particle size distribution and count, percent area coverage, or product performance criteria such as optical transmission or scatter. Several choices for witness surfaces are provided.

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 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 (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.

ASTM Standards

E1216 Practice for Sampling for Particulate Contamination by Tape Lift

F24 Test Method for Measuring and Counting Particulate Contamination on Surfaces

F312 Test Methods for Microscopical Sizing and Counting Particles from Aerospace Fluids on Membrane Filters

Government Standards

ISO Standard

Keywords

cleanroom; contamination control; controlled environment; Analyzing witness surfaces; Cleanrooms (materials/applications); Environmental control/fate; Particulate contamination (aerospace environments); Preparing witness surfaces; Selection guides--test procedures; Witness surfaces; Analyzing witness surfaces; Cleanrooms (materials/applications); Environmental control/fate; Particulate contamination (aerospace environments); Preparing witness surfaces; Selection guides--test procedures; Witness surfaces

ICS Code

ICS Number Code 13.040.35 (Cleanrooms and associated controlled environments)

Citing ASTM Standards

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