Active Standard ASTM G121 | Developed by Subcommittee: G04.02
Book of Standards Volume: 14.04
Historical (view previous versions of standard)
Significance and Use
This practice will be suitable to direct the preparation of test coupons with a known amount of contaminant on the surface. A standard test coupon is described and a list of contaminants that have typically been found in oxygen-enriched systems and components is provided.
These coupons shall be used in the evaluation of cleaning agents for oxygen-enriched systems and components. This will permit direct comparison within and between test facilities.
Materials used in other fluid handling systems such as nitrogen, helium, hydrogen, gasoline, etc. may also be prepared for evaluation by this practice.
1.1 This practice describes the procedure for the preparation of single- and double-sided contaminated metallic test coupons for the evaluation of cleaning agents. It is applicable for the evaluation of cleaning agents proposed for the cleaning of oxygen-enriched systems and components. It also is applicable to other systems where contamination is a concern.
1.2 Several classes of contaminants most likely to be found in oxygen-enriched systems and components are identified. However, if the user of this practice has identified contaminants not included in these classes, such identified contaminants may be substituted for the preparation of the test coupons.
1.3 Preparation of nonmetallic substrates is not addressed, although similar methodology may be used. Solvent and cleaning agent compatibility with the nonmetallic substrate should be verified prior to the preparation of the test coupons. Typical nonmetallic materials utilized in oxygen systems are contained in Guide G63.
1.4 This practice may involve hazardous materials, operations, and equipment. This practice does not purport to address all of the safety concerns associated with its use. It is the responsibility of whomever uses this practice to consult and 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.
ANSIB 46.1 Surface Texture (Surface Roughness, Waviness, and Lay)
D1193 Specification for Reagent Water
E1235 Test Method for Gravimetric Determination of Nonvolatile Residue (NVR) in Environmentally Controlled Areas for Spacecraft
F303 Practices for Sampling for Particles in Aerospace Fluids and Components
F312 Test Methods for Microscopical Sizing and Counting Particles from Aerospace Fluids on Membrane Filters
F324 Test Method for Nonvolatile Residue of Volatile Cleaning Solvents Using the Solvent Purity Meter
F331 Test Method for Nonvolatile Residue of Solvent Extract from Aerospace Components (Using Flash Evaporator)
G63 Guide for Evaluating Nonmetallic Materials for Oxygen Service
G94 Guide for Evaluating Metals for Oxygen Service
ICS Number Code 71.100.40 (Surface active agents)