scope:

1.1 These test methods cover the sampling and testing of electrical insulating boards. These boards are porous, usually fibrous sheets used for dielectric and structural purposes in electrical apparatus.

1.2 These test methods are not intended for testing vulcanized fibre or molded laminated sheets.

1.3 These test methods are applicable to board materials having a nominal thickness of at least 0.030 in. (0.76 mm).

Note 1-For materials thinner than 0.030 in. (0.76 mm) see Test Methods D202.

1.4 The test methods appear in the following sections:

ASTM Method Sections Reference Apparent Density 18 to 23 Aqueous Extract Characteristics 36 to 42 D 202 Ash Content 43 to 46 T 413 Compatibility with Dielectric 47 to 52 D 664, D 877, D 924, Liquids D 971, D 974, D 1169, D 1500, D 1816, D 3455, D 3487 Compressibility 79 to 85 Conditioning 11 D 685 Degree of Polymerization 86 to 89 D 4243 Dielectric Strength in Air 53 to 59 D 149 Dielectric Strength in Oil 60 to 65 D 149, D 2413, D 3426 Dimensions of Sheets 12 to 17 Moisture Content 31 to 35 D 644 Oil Absorption 72 to 78 Reports 10 Sampling 6 to 9 D 3636 Shrinkage 24 to 30 D 644 Tensile Properties 66 to 71 D 202

1.5 The values stated in inch-pound units are to be re- garded as the standard.

1.6 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 consult and establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use .