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2.8.2.: Classification criteria

2.8.2.1. Any self-reactive substance or mixture shall be considered for classification in this class as a self-reactive substance or mixture unless:
(a) they are explosives, according to the criteria given in 2.1;
(b) they are oxidising liquids or solids, according to the criteria given in 2.13 or 2.14, except that mixtures of oxidising substances, which contain 5 % or more of combustible organic substances shall be classified as self-reactive substances according to the procedure defined in 2.8.2.2;
(c) they are organic peroxides, according to the criteria given in 2.15;
(d) their heat of decomposition is less than 300 J/g; or
(e) their self-accelerating decomposition temperature (SADT) is greater than 75 °C for a 50 kg package ( 7 ).
2.8.2.2. Mixtures of oxidising substances, meeting the criteria for classification as oxidising substances, which contain 5 % or more of combustible organic substances and which do not meet the criteria mentioned in (a), (c), (d) or (e) in 2.8.2.1, shall be subjected to the self-reactive substances classification procedure;

Such a mixture showing the properties of a self-reactive substance type B to F (see 2.8.2.3) shall be classified as a self-reactive substance.

Where the test is conducted in the package form and the packaging is changed, a further test shall be conducted where it is considered that the change in packaging will affect the outcome of the test.

2.8.2.3. Self-reactive substances and mixtures shall be classified in one of the seven categories of ‘types A to G’ for this class, according to the following principles:
(a) any self-reactive substance or mixture which can detonate or deflagrate rapidly, as packaged, shall be defined as self-reactive substance TYPE A;
(b) any self-reactive substance or mixture possessing explosive properties and which, as packaged, neither detonates nor deflagrates rapidly, but is liable to undergo a thermal explosion in that package shall be defined as self-reactive substance TYPE B;
(c) any self-reactive substance or mixture possessing explosive properties when the substance or mixture as packaged cannot detonate or deflagrate rapidly or undergo a thermal explosion shall be defined as self-reactive substance TYPE C;
(d) any self-reactive substance or mixture which in laboratory testing:
(i) detonates partially, does not deflagrate rapidly and shows no violent effect when heated under confinement; or
(ii) does not detonate at all, deflagrates slowly and shows no violent effect when heated under confinement; or
(iii) does not detonate or deflagrate at all and shows a medium effect when heated under confinement;

shall be defined as self-reactive substance TYPE D;

(e) any self-reactive substance or mixture which, in laboratory testing, neither detonates nor deflagrates at all and shows low or no effect when heated under confinement shall be defined as self-reactive substance TYPE E;
(f) any self-reactive substance or mixture 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 shall be defined as self-reactive substance TYPE F;
(g) any self-reactive substance or mixture which, in laboratory testing, neither detonates in the cavitated state nor deflagrates at all and shows no effect when heated under confinement nor any explosive power, provided that it is thermally stable (SADT is 60 °C to 75 °C for a 50 kg package), and, for liquid mixtures, a diluent having a boiling point not less than 150 °C is used for desensitisation shall be defined as self-reactive substance TYPE G. If the mixture is not thermally stable or a diluent having a boiling point less than 150 °C is used for desensitisation, the mixture shall be defined as self-reactive substance TYPE F.

Where the test is conducted in the package form and the packaging is changed, a further test shall be conducted where it is considered that the change in packaging will affect the outcome of the test.

2.8.2.4. Criteria for temperature control

Self-reactive substances need to be subjected to temperature control if their SADT is less than or equal to 55 °C. Test methods for determining the SADT as well as the derivation of control and emergency temperatures are given in, Part II, section 28 of the ►M4  UN RTDG ◄ , Manual of Tests and Criteria. The test selected shall be conducted in a manner which is representative, both in size and material, of the package.