Class 5, Oxidizing Substances and Organic Peroxides

2.24 General

Substances are included in Class 5 if they are oxidizing substances or organic peroxides and meet the criteria for inclusion in one of the divisions of Class 5.

2.25 Divisions

Class 5 has two divisions:

(a) Class 5.1, Oxidizing Substances, which consists of substances that yield oxygen thereby causing or contributing to the combustion of other material, as determined in accordance with section 2.5.2 of Chapter 2.5 of the UN Recommendations; and

(b) Class 5.2, Organic Peroxides, which consists of substances that

(i) as determined in accordance with section 2.5.3 of Chapter 2.5 of the UN Recommendations, are thermally unstable organic compounds that contain oxygen in the bivalent "-O-O-" structure,

(ii) are liable to undergo exothermic self-accelerating decomposition,

(iii) have one or more of the following characteristics:

(A) are liable to explosive decomposition,

(B) burn rapidly,

(C) are sensitive to impact or friction,

(D) react dangerously with other dangerous goods, or

(E) cause damage to the eyes, or

(iv) are listed in Schedule 5.

If the substance to be classified appears as an entry in the first column of Schedule 5, the UN number is the one shown in the last column. That UN number is then used as the entry point into Schedule 2 to identify the remaining classification elements for the substance.

(1) The determination of packing groups for Class 5.1, Oxidizing Substances, must be made

(a) for solids, using a test sample of either a 4:1 or 1:1 mixture of substance and cellulose by mass, prepared and tested in accordance with section 2.5.2.2 of Chapter 2.5 of the UN Recommendations; or

(b) for liquids, using a test sample of a 1:1 mixture of substance and cellulose by mass, prepared and tested in accordance with section 2.5.2.3 of Chapter 2.5 of the UN Recommendations.

(2) Substances included in Class 5.1, Oxidizing Substances, are included in the following packing groups:

(a) for solids,

(i) Packing Group I, if the test sample exhibits an average burning time less than the mean burning time of a 3:2 mixture by mass of potassium bromate and cellulose,

(ii) Packing Group II, if the test sample exhibits an average burning time less than or equal to the mean burning time of a 2:3 mixture by mass of potassium bromate and cellulose and the criteria for inclusion in Packing Group I are not met, or

(iii) Packing Group III, if the test sample exhibits an average burning time less than or equal to the mean burning time of a 3:7 mixture by mass of potassium bromate and cellulose and the criteria for inclusion in Packing Group I or II are not met; or

(b) for liquids,

(i) Packing Group I, if spontaneous ignition occurs or the mean pressure rise time of a 1:1 mixture by mass of substance and cellulose is less than that of a 1:1 mixture by mass of 50 per cent perchloric acid and cellulose,

(ii) Packing Group II, if a mean pressure rise time occurs that is less than or equal to the mean pressure rise time of a 1:1 mixture by mass of 40 per cent aqueous sodium chlorate solution and cellulose and the criteria for inclusion in Packing Group I are not met, or

(iii) Packing Group III, if a mean pressure rise time occurs that is less than or equal to the mean pressure rise time of a 1:1 mixture by mass of 65 per cent aqueous nitric acid and cellulose and the criteria for inclusion in Packing Group I or II are not met.

(3) Class 5.2, Organic Peroxides, are included in Packing Group II.

(4) The type, A to F, of organic peroxides with the UN numbers 3101 to 3120, must be determined in accordance with section 2.5.3.3 of Chapter 2.5 of the UN Recommendations.

For the organic peroxides listed in Schedule 5, the determination of type has been made and is shown with the shipping name in column 1 of Schedule 1 or 2.