This specification covers unfaced flexible fibrous glass blanket and faced board used for thermal and sound absorbing insulation for military applications as a replacement for MIL-I-22023D. The fibrous glass felt shall be of the following types and grades: Types I and II (Grades 1, 2, 3, 4, 5, and 6). The insulation shall be composed of glass, processed from a molten state into a fibrous form, bonded with a chemical binder. The following test methods shall be performed: flexibility and rigidity; density; determining binder content; thermal conductivity; corrosiveness to steel; surface burning characteristics; determining the vibration resistance of fibrous glass insulation; maximum use temperature; and determination of flashover potential of a lining material using a quarter-scale room fire test.

1.1 This specification covers unfaced flexible fibrous glass blanket and faced board used for thermal and sound absorbing insulation at temperatures up to 450°F (232°C) for military applications as a replacement for MIL-I-22023D.

1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.

1.3 This specification measures and describes the response of materials, products, or assemblies to heat and flame under controlled conditions, but does not by itself incorporate all factors required for fire hazard or fire risk assessment of the materials, products, or assemblies under actual fire conditions.

1.4 The following hazard caveat pertains only to the test method section of this specification. 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.