Significance and Use
18.1 This test method provides useful engineering information for evaluating the mechanical behavior of rigid electrical insulation at elevated temperature. When the proper exposure and test temperatures are chosen, depending on the material and end-use operating temperature, use the test method as one means of indicating relative thermal degradation of rigid insulating materials.
Scope
1.1 These test methods cover procedures for testing rigid electrical insulation normally manufactured in flat sheet or plate form. They are generally used as terminal boards, spacers, voltage barriers, and circuit boards.
1.2 Use Test Methods D619 (withdrawn) or Specification D710 for tests applying to vulcanized fibre.
1.3 Some of the test methods contained in this standard are similar to those contained in IEC 60893-2, which applies to rigid industrial laminated sheets based on thermosetting resins for electrical purposes.
1.4 The test methods appear in the following sections:
| Test | Sections | ASTM |
| Acetone extractable matter | 83 to 84 | D494 |
| Arc resistance | 47 | D495 |
| Ash | 56 to 60 | ... |
| Bonding strength | 49 to 54 | ... |
| Burning rate and flame resistance | 61 to 75 | ... |
| Compressive strength | 25 | D695 |
| Conditioning | 4 | D6054 |
| Dissipation factor | 34 to 40 | D669 |
| Dielectric strength | 28 to 33 | D149 |
| Expansion (linear thermal) | 76 | D696 |
| Flexural properties | 12 to 24 | D790 |
| Hardness (Rockwell) | 55 | D785 |
| Insulation resistance and resistivity | 41 to 46 | D257 |
| Permittivity | 34 to 40 | D150 |
| Resistance to impact | 26 | D256 |
| Tensile properties |  7 to 11 | D638 |
| Thickness | 5 to 6 | D374 |
| Tracking resistance | 48 | D2132 |
| Warp or twist | 77 to 82 | ... |
| Water absorption | 27 | D570 |
1.5 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.
1.6 This is a fire-test-response standard. See Sections 61 through 75, which are the procedures for burning rate and flame resistance.
1.7 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 31.1 and 1.8.
1.8 This standard 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.
1.9 Fire testing is inherently hazardous. Adequate safeguards for personnel and property shall be employed in conducting these tests.
