1.1 This test method provides guidelines for acoustic emission (AE) examination of filament-wound composite pressure vessels, for example, the type used for fuel tanks in vehicles which use natural gas fuel.

1.2 This test method requires pressurization to a level equal to or greater than what is encountered in normal use. The tanks' pressurization history must be known in order to use this test method. Pressurization medium may be gas or liquid.

1.3 This test method is limited to vessels designed for less than 10 000 psi (689 bar) maximum allowable working pressure and water volume less than 2.5 ft³ (0.07 m³).

1.4 AE measurements are used to detect emission sources. Other nondestructive examination (NDE) methods may be used to evaluate the significance of AE sources. Procedures for other NDE methods are beyond the scope of this test method.

1.5 This test method applies to examination of new and in-service filament-wound composite pressure vessels.

1.6 This test method applies to examinations conducted at ambient temperatures above 70°F (21°C). This test method may be used at ambient temperatures below 70°F if provision has been made to fill to the tank's rated pressure at 70°F.

1.7 The values stated in inch-pound units are to be regarded as the standard. SI units which are in parentheses are for information only.

1.8 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. Specific precautionary statements are given in Section 8.