a) To the outer face of a specimen

a) To the outer face of a specimen mounted with the length direction of the material vertical, apply the butane flame for a duration of 2 s. Stop the timer by means of the manual stop button when the fabric ceases to flame, and note whether ignition, as defined in clause 3 or in an appropriate performance standard, has taken place. If ignition did not occur, and if the state of the specimen permits, turn the frame and specimen through 180° in a vertical plane and repeat but with a flame application time of 3 s. If the specimen did not ignite, repeat again but with fresh specimens as appropriate and with flame application times of 4, 6, 8 and 10 s until the shortest of these times, if any, is found that causes a specimen to ignite.b) Repeat a) but starting with a fresh specimen and at one time interval down the sequence of flame application times from the longest application time used in a) (unless this is 2 s, in which case start again at 2 s) and with the direction of the material at 180° to its direction at the corresponding time in a). If the result differs by 2 s or more from the result of a) repeat once more and report all values.c) Repeat a) and b) using specimens with a width direction of the material vertical.