A flame is applied to a vertically oriented textile fabric to determine the fire behavior.
A test specimen is oriented vertically on a specimen holder. A small flame is applied to the face of the specimen.
For type B the ease of ignition is observed, and if the flame reaches one of the edges of the specimen and if any flaming debris falls down.
For type C after-flame time and afterglow time have to be measured also.
The test material is judged by the observed characteristics.
The fabric has to be tested before and after laundering: type B requires 12 cycles of BS EN ISO 10528 (Standard Washing Procedure) at 75°C and then line dried, type C requires 50 cycles of BS EN ISO 10528 (Standard Washing Procedure) @ 75°C and then low heat and then tumble dried.