Cal. Code Regs. tit. 19 § 1273.3
After removing the fabric from the test flame, the specimen shall not continue to flame for more than two seconds. Exception is made for short duration flaming, in accumulated char areas, which produces no flame spread or travel. No flames shall reach the top of the specimen.
Three specimens each one foot (1') wide by two and one-half feet (2 1/2') long shall be tested for fire resistance.
Each specimen shall be suspended, [FN*] with its lower edge approximately two inches (2") in the test flame, and not less than a twenty-four inch (24") length exposed. The test flame from a three-eighths inch (3/8") I.D. Bunsen burner, with the air supply just sufficient to remove all traces of yellow flame, but without any distinct blue inner cone, adjusted to a length between three and one-half inches (3 1/2") and four inches (4") shall be applied vertically at the center of the lower edge. No exposure time limitation is imposed, since every effort must be made to initiate sustained combustion.
Failing to ignite the area originally exposed, the specimen should be moved to expose an area near either vertical edge.
Cal. Code Regs. Tit. 19, § 1273.3
Suspension shall be by means of a wooden dowel held in the hand, with the upper end of the free hanging specimen rolled around the dowel tightly enough to remain in place, and without restraint by clamps or guide wires.