(i) The term "compressed gas" shall designate any material or mixture having in the container an
absolute pressure exceeding 40 p.s.i. at 70 °F or, regardless of the pressure at 70 °F, having an
absolute pressure exceeding 104 p.s.i. at 130 °F; or any liquid flammable material having a vapor
pressure exceeding 40 p.s.i. absolute at 100 °F as determined by ASTM Test D–323.
(ii) A compressed gas shall be characterized as ignitable if any one of the following occurs:
(A) Either a mixture of 13 percent or less (by volume) with air forms a flammable mixture or the
flammable range with air is wider than 12 percent regardless of the lower limit. These limits
shall be determined at atmospheric temperature and pressure. The method of sampling and test
procedure shall be acceptable to the Bureau of Explosives and approved by the director, Pipeline
and Hazardous Materials Technology, U.S. Department of Transportation (see Note 2).
(B) Using the Bureau of Explosives' Flame Projection Apparatus (see
Note 1), the flame projects
more than 18 inches beyond the ignition source with valve opened fully, or, the flame flashes
back and burns at the valve with any degree of valve opening.
(C) Using the Bureau of Explosives' Open Drum Apparatus (see
Note 1), there is any significant
propagation of flame away from the ignition source.
(D) Using the Bureau of Explosives' Closed Drum Apparatus (see Note 1), there is any explosion
of the vapor-air mixture in the drum.
Letters/Memoranda
•
INCINERATORS THAT RECEIVE GASEOUS EMISSIONS, RCRA EXCLUSION, CAA APPLIES
Regulations for Oxidizers
§ 261.21(a)
(4) It is an oxidizer. An oxidizer for the purpose of this subchapter is a substance such as a
chlorate, permanganate, inorganic peroxide, or a nitrate, that yields oxygen readily to stimulate
the combustion of organic matter (see Note 4).
(i) An organic compound containing the bivalent -O-O- structure and which may be considered a
derivative of hydrogen peroxide where one or more of the hydrogen atoms have been replaced
by organic radicals must be classed as an organic peroxide unless:
(A) The material meets the definition of a Class A explosive or a Class B explosive, as defined in
§261.23(a)(8), in which case it must be classed as an explosive,
(B) The material is forbidden to be offered for transportation according to
49 CFR 172.101
and 49 CFR 173.21,
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