High-Current Arc Ignition
(HAI) UL 746A - National Technical Systems (NTS)
High-Current Arc Ignition (HAI) performance is expressed as the number of arc rupture exposures (standardized to the electrode type and shape and electric circuit) that are necessary to ignite a material when they are applied at a standard rate on the surface of the material. The number of arc rupture exposures necessary to ignite a material when they are applied at a standard rate on the surface of the material. Performance Level Categories (PLC) were introduced to avoid excessive implied precision and bias.