Sets out a method for the non-destructive measurement of coating thickness using beta-backscatter gauges. Applies to both metallic and non-metallic coatings on both metallic and non-metallic substrates.

This Standard specifies a method for the non-destructive measurement of coating thicknesses using beta-backscatter gauges. It applies to both metallic and non-metallic coatings on both metallic and non-metallic substrates. To employ this method, the atomic numbersor equivalent atomic numbers of the coating and the substrate need to differ by an appropriate amount.WARNING: BETA-BACKSCATTER INSTRUMENTS USED FOR THE MEASUREMENT OF COATING THICKNESSES EMPLOY A NUMBER OF DIFFERENT RADIOACTIVE SOURCES. ALTHOUGH THE ACTIVITIES OF THESE SOURCES ARE NORMALLY VERY LOW, THEY CAN PRESENT A HAZARD TO HEALTH, IF INCORRECTLY HANDLED. THEREFORE, ALL RULES AND REGULATIONS OF LOCAL OR NATIONAL AUTHORITIES MUST BE OBSERVED.NOTES:1 Characteristics of isotopes used with beta-backscatter gauges are given in Appendix A.2 The atomic numbers of some commonly used coatings and substrates are given in Appendix B.

First published as part of AS K173-1971.Revised and redesignated in part as AS 2331.1.5-1981.Second edition 2001.Reconfirmed 2017. Originated as part of AS K173-1971. Previous edition AS 2331.1.5-1981. Second edition 2001.