What is ASTM fire testing?
Like the UL94 tests, the ASTM fire testing has five types of fire tests to compare plastic materials in terms of their burning behaviour. Each type of test requires a specific gas flow rate, flame height, specimen and flame orientation, and time of exposure to the flame. Likewise, measurements such as afterflame times, afterglow times, and burning rate are performed. The results obtained are then compared against a standard set of test criteria and the material is given a rating based on the criteria it satisfies.
The figure, seen right, illustrates the flammability of material in relation to the ratings assigned, 5VA/VB being the least flammable while HB/HBF being the most flammable.
More ASTM Flammability Testing
| test/activity | rating | application |
| ASTM D635 | HB | Polymeric materials used for parts in devices and appliances. |
| ASTM D3801 | V-0, V-1 or V-2 | Polymeric materials used for parts in devices and appliances. Cannot be used to classify materials used in building construction or finishing. |
| ASTM D5048 | 5VA or 5VB | Polymeric materials used for parts in devices and appliances. Cannot be used to classify materials used in building construction or finishing. Can be used to classify non-metallic materials if found appropriate. |
| ASTM D4804 | VTM-0,VTM-1 or VTM-2 | Plastic materials to be used as very thin films, generally not capable of supporting themselves in a horizontal position. These are usually assigned to substrates on flexible printed circuit boards. |
| ASTM D4986 | HBF, HF-1 or HF-2 | Low density foam materials. |
