
[Code of Federal Regulations]
[Title 30, Volume 1]
[Revised as of July 1, 2001]
From the U.S. Government Printing Office via GPO Access
[CITE: 30CFR7]

[Page 16-19]
 
                       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. 7.21  Purpose and effective date.

    This subpart establishes the specific requirements for approval of 
brattice cloth and ventilation tubing. It is effective August 22, 1988. 
Applications for approval or extension of approval submitted after 
August 22, 1989, shall meet the requirements of this part.

Sec. 7.22  Definitions.

    The following definitions apply in this subpart:
    Brattice cloth. A curtain of jute, plastic, or similar material used 
to control or direct ventilating air.
    Denier. A unit of yarn size indicating the fineness of fiber of 
material based on the number of grams in a length of 9,000 meters.
    Film. A sheet of flexible material applied to a scrim by pressure, 
temperature, adhesion, or other method.
    Scrim. A substrate material of plastic or fabric laminated between 
or coated with a film.
    Ventilation tubing. Rigid or flexible tubing used to convey 
ventilating air.

Sec. 7.23  Application requirements.

    (a) Brattice cloth. A single application may address two or more 
products if the products differ only in: weight of the finished product; 
weight or weave of the same fabric or scrim; or thickness or layers of 
the same film. Applications shall include the following information:
    (1) Trade name.
    (2) Product designations (for example, style and code number).
    (3) Color.
    (4) Type of brattice (for example, plastic or jute).
    (5) Weight of finished product.
    (6) Film: type, weight, thickness, supplier, supplier's stock number 
or designation, and percent of finished product by weight.
    (7) Scrim: Type, denier, weight, weave, the supplier, supplier's 
stock number or designation, and percent of finished product by weight.
    (8) Adhesive: type, supplier, supplier's stock number or 
designation, and percent of finished product by weight.
    (b) Flexible ventilation tubing. Applications shall include the 
product description information in paragraph (a) of this section and 
list the type of supporting structure, if applicable; inside diameters; 
and configurations.
    (c) Rigid ventilation tubing. A single application may address two 
or more products if the products differ only in diameters, lengths, 
configuration, or average wall thickness. Applications

[[Page 17]]

shall include the following information:
    (1) Trade name.
    (2) Product designations (for example, style and code numbers).
    (3) Color.
    (4) Type of ventilation tubing (for example, fiberglass, plastic, or 
polyethylene).
    (5) Inside diameter, configuration, and average wall thickness.
    (6) Suspension system (for example, metal hooks).
    (7) Base material: type, supplier, the supplier's stock number, and 
percent of finished product by weight.
    (8) Resin: type, supplier, the supplier's stock number, and percent 
of finished product by weight.
    (9) Flame retardant, if added during manufacturing: type, supplier, 
the supplier's stock number, and percent of finished product by weight.

[53 FR 23500, June 22, 1988, as amended at 60 FR 33722, June 29, 1995]

Sec. 7.24  Technical requirements.

    (a) Brattice cloth shall be flame resistant when tested in 
accordance with the flame resistance test in Sec. 7.27.
    (b) Flexible ventilation tubing shall be manufactured using an MSHA-
approved brattice cloth. If a supporting structure is used, it shall be 
metal or other noncombustible material which will not ignite, burn, 
support combustion or release flammable vapors when subjected to fire or 
heat.
    (c) Rigid ventilation tubing shall be flame resistant when tested in 
accordance with the flame resistance test in Sec. 7.28.

Sec. 7.25  Critical characteristics.

    A sample of each batch or lot of brattice cloth and ventilation 
tubing shall be flame tested or a sample of each batch or lot of the 
materials that contribute to the flame-resistance characteristic shall 
be inspected or tested to ensure that the finished product will meet the 
flame-resistance test.

Sec. 7.26  Flame test apparatus.

    The principal parts of the apparatus used to test for flame-
resistance of brattice cloth and ventilation tubing shall be constructed 
as follows:
    (a) A 16-gauge stainless steel gallery lined on the top, bottom and 
both sides with \1/2\ inch thick Marinite or equivalent insulating 
material yielding inside dimensions approximately 58 inches long, 41 
inches high, and 30 inches wide;
    (b) Two \3/8\-inch diameter steel J hooks and a \9/16\-inch diameter 
steel rod to support the sample located approximately 2\3/16\-inches 
from the front and back ends of the test gallery, 1\1/2\-inches from the 
ceiling insulation and centrally located in the gallery along its 
length. Samples shall be suspended to preclude folds or wrinkles;
    (c) A tapered 16-gauge stainless steel duct section tapering from a 
cross sectional area measuring 2 feet 7 inches wide by 3 feet 6 inches 
high at the test gallery to a cross-sectional area 1 foot 6 inches 
square over a length of 3 feet. The tapered duct section must be tightly 
connected to the test gallery;
    (d) A 16-gauge stainless steel fan housing, consisting of a 1 foot 6 
inches square section 6 inches long followed by a 10 inch long section 
which tapers from 1 foot 16 inches square to 12 inches diameter round 
and concluding with a 12 inch diameter round collar 3 inches long. A 
variable speed fan capable of producing an air velocity of 125 ft./min. 
in the test gallery must be secured in the fan housing. The fan housing 
must be tightly connected to the tapered duct section;
    (e) A methane-fueled impinged jet burner igniting source, measuring 
12 inches long from the threaded ends of the first and last jets and 4 
inches wide with 12 impinged jets, approximately 1\3/8\-inches long and 
spaced alternately along the length of the burner tube. The burner jets 
must be canted so that they point toward each other in pairs and the 
flame from these pairs impinge upon each other.

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 70<plus-minus>10  deg.F (21<plus-minus>5.5 
deg.C) and a relative humidity of 55<plus-minus>10%.
    (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]

Sec. 7.28  Test for flame resistance of rigid ventilation tubing.

    (a) Test procedures. (1) Prepare 6 samples of ventilation tubing 48 
inches in length with all flared or thickened ends removed. Any sample 
with a cross-sectional dimension greater than 24 inches must be tested 
in a 24-inch size.
    (2) For each test, suspend the sample in the center of the gallery 
by running a wire through the 48-inch length of tubing.
    (3) 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.
    (4) Set the methane-fueled impinged jet burner to yield a flame 
height of 12 inches as measured at the outermost tip of the flame.
    (5) Apply the burner to the front lower edge of the tubing so that 
two-thirds of the burner is under the tubing and the remaining third is 
exposed to allow the flames to curl onto the inside of the tubing. Keep 
the burner in contact with the material for 60 seconds. If melting 
material might clog the burner orifices, rotate the burner slightly 
during application of the flame.
    (6) Test 3 samples in still air and 3 samples with an average of 125 
ft./min. of air flowing past the sample.
    (7) Record the propagation length and duration of burning for each 
of the 6 samples. The duration of burn is the total burning time of the 
specimen during the flame test. This includes the burning 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 burn time 
only once.
    (8) Calculate the average duration of burning for the first 3 
samples (still air) and the second 3 samples (125 ft./min. air flow).

[[Page 19]]

    (b) Acceptable performance. The ventilation tubing shall meet each 
of the following criteria:
    (1) Flame propagation of less than 4 feet in each of the 6 tests.
    (2) An average duration of burning of less than 1 minute in both 
groups of 3 tests.
    (3) A duration of burning not exceeding 2 minutes in each of the 6 
tests.

[53 FR 23500, June 22, 1988, as amended at 60 FR 33723, June 29, 1995]

Sec. 7.29  Approval marking.

    (a) Approved brattice cloth shall be legibly and permanently marked 
with the assigned MSHA approval number at intervals not exceeding ten 
feet. If the nature of the material or method of processing makes such 
marking impractical, permanent paint or ink may be used to mark the edge 
with an MSHA-assigned color code.
    (b) Approved ventilation tubing shall be legibly and permanently 
marked on each section with the assigned MSHA approval number.
    (c) An approved product shall be marketed only under a brand or 
trade name that has been furnished to MSHA.

Sec. 7.30  Post-approval product audit.

    Upon request by MSHA but no more than once a year except for cause, 
the approval-holder shall supply to MSHA at no cost up to fifty feet of 
each approved design of brattice cloth and ventilation tubing for audit.

Sec. 7.31  New technology.

    MSHA may approve brattice cloth and ventilation tubing that 
incorporates technology for which the requirements of this subpart are 
not applicable, if the Agency determines that the product is as safe as 
those which meet the requirements of this subpart.
