UL 1666 Flammability Test

This is a fire test for determining values of flame propagation height for electrical cables that are for installation vertically in shafts or in vertical runs that penetrate more than one floor.

Two sets of specimens of each cable construction are to be tested, each set is to consist of multiple 5.33 m specimen lengths of cable. Fixed vertically in a 2.44m long, 5.80m high chamber.

The test flame is to be applied to the cable specimens for 30 min. The flame propagation height of each set of cable specimens shall not equal or exceed 3.66 m. The temperature of any thermocouple shall not exceed 454.4°C.