[Code of Federal Regulations]
[Title 30, Volume 1]
[Revised as of July 1, 2002]
From the U.S. Government Printing Office via GPO Access
[CITE: 30CFR7.27]
[Page 17-18]
TITLE 30--MINERAL RESOURCES
CHAPTER I--MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR
PART 7--TESTING BY APPLICANT OR THIRD PARTY--Table of Contents
Subpart B--Brattice Cloth and Ventilation Tubing
Sec. 7.27 Test for flame resistance of brattice cloth.
(a) Test procedures. (1) Prepare 6 samples of brattice cloth 40
inches wide by 48 inches long.
(2) Prior to testing, condition each sample for a minimum of 24
hours at a temperature of 7010 deg.F (215.5
deg.C) and a relative humidity of 5510%.
(3) For each test, suspend the sample in the gallery by wrapping the
brattice
[[Page 18]]
cloth around the rod and clamping each end and the center. The brattice
cloth must hang 4 inches from the gallery floor.
(4) Use a front exhaust system to remove smoke escaping from the
gallery. The exhaust system must remain on during all testing, but not
affect the air flow in the gallery.
(5) Set the methane-fueled impinged jet burner to yield a flame
height of 12 inches as measured at the outermost tip of the flame.
(6) Apply the burner to the front lower edge of the brattice cloth
and keep it in contact with the material for 25 seconds or until 1 foot
of material, measured horizontally, is consumed, whichever occurs first.
If the material shrinks during application of the burner flame, move the
burner flame to maintain contact with 1 foot of the material. If melting
material might clog the burner orifices, rotate the burner slightly
during application of the flame.
(7) Test 3 samples in still air and 3 samples with an average of 125
ft./min. of air flowing past the sample.
(8) Record the propagation length and duration of burning for each
of the 6 samples. The duration of burning is the total burning time of
the specimen during the flame test. This includes the burn time of any
material that falls on the floor of the test gallery during the igniting
period. However, the suspended specimen is considered burning only after
the burner is removed. Should the burning time of a suspended specimen
and a specimen on the floor coincide, count the coinciding burning time
only once.
(9) Calculate the average duration of burning for the first 3
samples (still air) and the second 3 samples (125 ft./min. air flow).
(b) Acceptable performance. The brattice cloth shall meet each of
the following criteria:
(1) Flame propagation of less than 4 feet in each of the six tests.
(2) An average duration of burning of less than 1 minute in both
groups of three tests.
(3) A duration of burning not exceeding two minutes in each of the
six tests.
[53 FR 23500, June 22, 1988, as amended at 60 FR 33723, June 29, 1995]