[Code of Federal Regulations]
[Title 16, Volume 2]
[Revised as of January 1, 2007]
From the U.S. Government Printing Office via GPO Access
[CITE: 16CFR1611.4]

[Page 621-623]
 
                     TITLE 16--COMMERCIAL PRACTICES
 
             CHAPTER II--CONSUMER PRODUCT SAFETY COMMISSION
 
PART 1611_STANDARD FOR THE FLAMMABILITY OF VINYL PLASTIC FILM--Table 
of Contents
 
                         Subpart A_The Standard
 
Sec.  1611.4  Flammability test.

    (a) Apparatus and materials. The apparatus shall be constructed 
essentially as shown in figure 1 and shall consist of the following:
    (1) Specimen holder. (i) A removable, flat, specimen-holding rack, 
the upper and lower sections of which are separate, shall have the shape 
and dimensions shown in figure 2 (sketch of sample-holding rack). The 
specimen is supported by tight closure of the upper and lower sections 
around the sides of the specimen. The center section of the rack 
contains an open U-shaped area in which burning of the specimen takes 
place. At the open end of the rack the forked sides are at an angle of 
45[deg] for the last inch. Thus, when the rack is slid into the cabinet 
on runners mounted at a 45[deg] angle, the bent portion of the specimen 
adjacent to the igniter flame is vertical and the remainder is at 
45[deg].
    (ii) The switch actuators consist of suitable springs mounted on the 
side of the rack, one just beyond the curved portion at the open end, 
and the other at the closed end of the U-shaped holder. The springs are 
depressed and held in position prior to ignition by means of cotton 
thread suitably wound across the specimen and securely attached to the 
rack. As flame reaches these threads, the springs are released, thus 
activating the microswitches of the stop clocks.
    (2) Igniter flame. The igniter flame shall be produced at the tip of 
a No. 22

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hypodermic needle jet. The igniter shall be so located in the cabinet 
that the tip of the needle is \9/16\ in. from the surface of the 
specimen when the specimen rack is in place.
    (3) Cabinet. The cabinet shall protect the igniter flame and 
specimen from air currents during tests, yet contain a suitable door or 
window for visual operation, provision for inserting the specimen 
holder, and adjustable vents to supply sufficient air for combustion of 
the specimen. It should also be capable of rapid ventilation following a 
test so that all combustion products can be removed between tests. A 
hood may be used if its exhaust fan is turned off during the test.
    (4) Timing mechanism. The burning rate shall be determined by a stop 
clock through microswitches mounted on the specimenholder rack. The 
clock is started when the specimen flame burns the first thread, and is 
stopped when the thread at the upper end of the holder, 6 in. from the 
first thread, burns apart. The timing mechanism shall be capable of 
indicating time interval to 0.1 second.
    (5) Butane. Unless otherwise specified, butane gas shall be used for 
the igniter flame.
    (6) Thread. J. & P. Coats heavy-duty white cotton thread.
    (7) Microburner.
    (b) Test specimens. (1) Test specimens shall be 3 in. in width and 9 
in. in length. They shall be free from folds or wrinkles. Five specimens 
from each direction (machine and transverse) of a given material shall 
be tested.
    (2) Conditioning. The conditioning procedure shall conform to the 
requirements of procedure B of ASTM D618, Tentative Methods of 
Conditioning Plastics and Electrical Insulating Materials for Testing.
    (c) Procedure. (1) After preparing the specimens, the holder shall 
be threaded so as to depress the switch actuators (springs) at least \1/
4\ in. from the edge of the holder. Each actuator shall be separately 
threaded, the thread passing down through the J-slots and under the 
upper jaws so that the thread is adjacent to the specimen when the 
holder is closed.
    (2) The specimen shall be inserted into the holder so that it 
extends down into the lock springs and is held firmly between the two 
wires at the open end of the burning channel. These wires insure that 
the end of the specimen is always the correct distance from the igniter 
flame. The sample shall be free from wrinkles or distortion when the 
holder is closed. The specimen should not extend beyond the outer edge 
of the lower plate, otherwise the rack may not slide freely on the slide 
channel on introducing it into the cabinet.
    (3) Prior to introducing the specimen and holder into the cabinet, 
both electrical switches shall be set for automatic timing. The needle 
valve regulating the butane flow shall be adjusted to provide a \1/2\-
in. flame. (When the specimen is in place its surface is \9/16\ in. from 
the tip of the needle and the flame is just barely flattened against the 
specimen. This can be checked by using a specimen made of asbestos in 
place of a plastic specimen.)
    (4) With the hood fan off, clocks zeroed, and the flame adjusted as 
mentioned, the door is closed and the specimen holder is then inserted 
at a constant rate. The holder should be allowed to slide down the rails 
by gravity, taking about one-half second to travel the length of the 
slide. Any hesitation in bringing the specimen holder fully into burning 
position may cause erroneous ignition results.
    (5) The burning time shall be read from the stop clock and the rate 
of burning calculated. Results that deviate from the mean value of all 
tests should be rejected if the deviation of the doubtful value is more 
than five times the average deviation from the mean obtained by 
excluding the doubtful value. Such doubtful values shall be discarded 
and retests made.

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[GRAPHIC] [TIFF OMITTED] TC03OC91.079

[GRAPHIC] [TIFF OMITTED] TC03OC91.080


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