The dangers of smoke in fire incidents are threefold and include impaired visibility, exposure to toxic gases, and evacuation panic. ASTM E662 considers these issues through the measurement of the definite optical density of smoke under controlled laboratory conditions. The test identifies the extent to which materials cause smoke formation, both with and without flame, and even in smoldering conditions. It finds extensive application in regulatory testing, product qualification, and safety certification. The test has come to be recognized internationally as a standard test for measuring smoke density. Building material, electrical insulation, aerospace interior, and transportation equipment makers use it to confirm conformance with safety regulations. The test results are part of the basis for risk assessments and code compliance planning, which makes ASTM E662 an essential tool in contemporary fire safety engineering.
ASTM E662 Test Method
| Flaming Combustion Test | A 25 mm methane gas flame is applied to the specimen; the smoke optical density is measured continuously using a photometric system. |
| Non-Flaming (Radiant Heat) Test | Specimen is exposed to a controlled radiant heat flux of 2.5 W/cm² without an ignition source, monitoring smoke obscuration. |
| Optical Density Measurement | A photometer measures light attenuation through the chamber, calculating specific optical density over time. |
