Over the years leak detection techniques have varied from the use of simple household soap-based solutions to specialized leak detection fluids (LDFs). These specialized LDFs are far superior to household soap-based solutions that can contain contaminants or other detrimental constituents. As such, household soap-based solutions should not be used.

There are various national regulations and international guidelines to ensure that cylinders and valves are checked for leak tightness. Though such a postfill check is an essential part of a quality control procedure to ensure that customers receive a nonleaking package, the choice of the LDF needs to be carefully considered because of potential hazards from LDFs. These potential hazards include inducing stress corrosion cracking (SCC) and incompatibility with materials and cylinder contents such as oxygen.

This publication applies to gas cylinder packages. It covers the selection and use of specialized LDFs that are suitable for industrial gases including medical and food gases that have particular compatibility requirements.

This publication may be used as a guideline when fluids are used for leak detection in other gas applications.