What are UL-94 flammability ratings?
UL-94 flammability ratings are testing standards developed by Underwriters Laboratories to measure the flammability characteristics of plastic. There are six UL 94 specified flame classifications that apply to plastic enclosures used to house electronics (5VA, 5VB, V-0, V-1, V-2, HB).
These ratings are used to distinguish a material’s burning characteristics after test pieces have been exposed to a test flame under controlled laboratory conditions as summarized below:
Plastics meeting UL 94-5VA or UL 94-5VB have been tested with a flame source five times more severe than what is used in the remaining four tests, plus they are not allowed to have any flaming drips. These are considered to be the most flame-retardant plastics. Polycase offers several enclosure series meeting the UL 94-5VA flame rating, like the XR Series or DC Series.