4.1 The results obtained by this practice shall serve as a guide in, but not as the sole basis for, selection of a thermosetting resin used in an RTP structure. No attempt has been made to incorporate into the practice all the various factors that will potentially affect the serviceability of an RTP structure when subjected to chemical environments. These factors will potentially include stress, different resin-to-glass ratios, and multiple veils.

1.1 This practice is designed to evaluate, in an unstressed state, the chemical resistance of thermosetting resins used in the fabrication of reinforced thermosetting plastic (RTP) laminates. This practice provides for the determination of changes in the properties, described as follows, of the test specimens and test reagent after exposure of the specimens to the reagent: hardness of specimens, weight change thickness, appearance of specimens, appearance of immersion media, and flexural strength and modulus.

1.1.1 This practice is also useful to evaluate other factors, such as surfacing veils and the effect of resin additives, on the chemical resistance of the resin.

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.

Note 1: There is no known ISO equivalent to this standard.

1.3 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.