[Code of Federal Regulations]
[Title 49, Volume 2]
[Revised as of October 1, 2002]
From the U.S. Government Printing Office via GPO Access
[CITE: 49CFR173.124]

[Page 478-480]
 
                        TITLE 49--TRANSPORTATION
 
 CHAPTER I--RESEARCH AND SPECIAL PROGRAMS ADMINISTRATION, DEPARTMENT OF 
                             TRANSPORTATION
 
PART 173--SHIPPERS--GENERAL REQUIREMENTS FOR SHIPMENTS AND PACKAGINGS--Table of Contents
 
  Subpart D--Definitions Classification, Packing Group Assignments and 
    Exceptions for Hazardous Materials Other Than Class 1 and Class 7
 
Sec. 173.124  Class 4, Divisions 4.1, 4.2 and 4.3--Definitions.

    (a) Division 4.1 (Flammable Solid). For the purposes of this 
subchapter, flammable solid (Division 4.1) means any of the following 
three types of materials:
    (1) Desensitized explosives that--
    (i) When dry are Explosives of Class 1 other than those of 
compatibility group A, which are wetted with sufficient water, alcohol, 
or plasticizer to suppress explosive properties; and
    (ii) Are specifically authorized by name either in the 
Sec. 172.101Table or have been assigned a shipping name and hazard class 
by the Associate Administrator under the provisions of--
    (A) An exemption issued under subchapter A of this chapter; or
    (B) An approval issued under Sec. 173.56(i) of this part.
    (2)(i) Self-reactive materials are materials that are thermally 
unstable and that can undergo a strongly exothermic decomposition even 
without participation of oxygen (air). A material is excluded from this 
definition if any of the following applies:
    (A) The material meets the definition of an explosive as prescribed 
in subpart C of this part, in which case it must be classed as an 
explosive;
    (B) The material is forbidden from being offered for transportation 
according to Sec. 172.101 of this subchapter or Sec. 173.21;
    (C) The material meets the definition of an oxidizer or organic 
peroxide as prescribed in subpart D of this part, in which case it must 
be so classed;
    (D) The material meets one of the following conditions:
    (1) Its heat of decomposition is less than 300 J/g; or
    (2) Its self-accelerating decomposition temperature (SADT) is 
greater than 75  deg.C (167  deg.F) for a 50 kg package; or

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    (E) The Associate Administrator has determined that the material 
does not present a hazard which is associated with a Division 4.1 
material.
    (ii) Generic types. Division 4.1 self-reactive materials are 
assigned to a generic system consisting of seven types. A self-reactive 
substance identified by technical name in the Self-Reactive Materials 
Table in Sec. 173.224 is assigned to a generic type in accordance with 
that table. Self-reactive materials not identified in the Self-Reactive 
Materials Table in Sec. 173.224 are assigned to generic types under the 
procedures of paragraph (a)(2)(iii) of this section.
    (A) Type A. Self-reactive material type A is a self-reactive 
material which, as packaged for transportation, can detonate or 
deflagrate rapidly. Transportation of type A self-reactive material is 
forbidden.
    (B) Type B. Self-reactive material type B is a self-reactive 
material which, as packaged for transportation, neither detonates nor 
deflagrates rapidly, but is liable to undergo a thermal explosion in a 
package.
    (C) Type C. Self-reactive material type C is a self-reactive 
material which, as packaged for transportation, neither detonates nor 
deflagrates rapidly and cannot undergo a thermal explosion.
    (D) Type D. Self-reactive material type D is a self-reactive 
material which--
    (1) Detonates partially, does not deflagrate rapidly and shows no 
violent effect when heated under confinement;
    (2) Does not detonate at all, deflagrates slowly and shows no 
violent effect when heated under confinement; or
    (3) Does not detonate or deflagrate at all and shows a medium effect 
when heated under confinement.
    (E) Type E. Self-reactive material type E is a self-reactive 
material which, in laboratory testing, neither detonates nor deflagrates 
at all and shows only a low or no effect when heated under confinement.
    (F) Type F. Self-reactive material type F is a self-reactive 
material which, in laboratory testing, neither detonates in the 
cavitated state nor deflagrates at all and shows only a low or no effect 
when heated under confinement as well as low or no explosive power.
    (G) Type G. Self-reactive material type G is a self-reactive 
material which, in laboratory testing, does not detonate in the 
cavitated state, will not deflagrate at all, shows no effect when heated 
under confinement, nor shows any explosive power. A type G self-reactive 
material is not subject to the requirements of this subchapter for self-
reactive material of Division 4.1 provided that it is thermally stable 
(self-accelerating decomposition temperature is 50  deg.C (122  deg.F) 
or higher for a 50 kg (110 pounds) package). A self-reactive material 
meeting all characteristics of type G except thermal stability is 
classed as a type F self-reactive, temperature control material.
    (iii) Procedures for assigning a self-reactive material to a generic 
type. A self-reactive material must be assigned to a generic type based 
on--
    (A) Its physical state (i.e. liquid or solid), in accordance with 
the definition of liquid and solid in Sec. 171.8 of this subchapter;
    (B) A determination as to its control temperature and emergency 
temperature, if any, under the provisions of Sec. 173.21(f);
    (C) Performance of the self-reactive material under the test 
procedures specified in the UN Recommendations on the Transport of 
Dangerous Goods, Tests and Criteria (see Sec. 171.7 of this subchapter) 
and the provisions of paragraph (a)(2)(iii) of this section; and
    (D) Except for a self-reactive material which is identified by 
technical name in the Self-Reactive Materials Table in Sec. 173.224(b) 
or a self-reactive material which may be shipped as a sample under the 
provisions of Sec. 173.224, the self-reactive material is approved in 
writing by the Associate Administrator. The person requesting approval 
shall submit to the Associate Administrator the tentative shipping 
description and generic type and--
    (1) All relevant data concerning physical state, temperature 
controls, and tests results; or
    (2) An approval issued for the self-reactive material by the 
competent authority of a foreign government.
    (iv) Tests. The generic type for a self-reactive material must be 
determined

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using the testing protocol from Figure 14.2 (Flow Chart for Assigning 
Self-Reactive Substances to Division 4.1) from the UN Recommendations on 
the Transport of Dangerous Goods, Tests and Criteria.
    (3) Readily combustible solids are materials that--
    (i) Are solids which may cause a fire through friction, such as 
matches;
    (ii) Show a burning rate faster than 2.2 mm (0.087 inches) per 
second when tested in accordance with UN Manual of Tests and Criteria; 
or
    (iii) Any metal powders that can be ignited and react over the whole 
length of a sample in 10 minutes or less, when tested in accordance with 
UN Manual of Tests and Criteria.
    (b) Division 4.2 (Spontaneously Combustible Material). For the 
purposes of this subchapter, spontaneously combustible material 
(Division 4.2) means--
    (1) A pyrophoric material. A pyrophoric material is a liquid or 
solid that, even in small quantities and without an external ignition 
source, can ignite within five (5) minutes after coming in contact with 
air when tested according to UN Manual of Tests and Criteria.
    (2) A self-heating material. A self-heating material is a material 
that, when in contact with air and without an energy supply, is liable 
to self-heat. A material of this type which exhibits spontaneous 
ignition or if the temperature of the sample exceeds 200  deg.C (392 
deg.F) during the 24-hour test period when tested in accordance with UN 
Manual of Tests and Criteria, is classed as a Division 4.2 material.
    (c) Division 4.3 (Dangerous when wet material). For the purposes of 
this chapter, dangerous when wet material (Division 4.3) means a 
material that, by contact with water, is liable to become spontaneously 
flammable or to give off flammable or toxic gas at a rate greater than 1 
L per kilogram of the material, per hour, when tested in accordance with 
UN Manual of Tests and Criteria.

[Amdt. 173-224, 55 FR 52634, Dec. 21, 1990, as amended at 56 FR 66268, 
Dec. 20, 1991; 57 FR 45461, Oct. 1, 1992; Amdt. 173-233, 58 FR 33305, 
June 16, 1993; Amdt. 173-234, 58 FR 51532, Oct. 1, 1993; Amdt. 173-241, 
59 FR 67507, Dec. 29, 1994; Amdt. 173-261, 62 FR 24731, May 6, 1997; 66 
FR 8647, Feb. 1, 2001; 66 FR 45379, Aug. 28, 2001]