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Transportation of Dangerous Goods Regulations (SOR/2001-286)

Regulations are current to 2020-11-02 and last amended on 2020-02-19. Previous Versions

PART 2Classification (continued)

Class 4, Flammable Solids; Substances Liable to Spontaneous Combustion; Substances That on Contact with Water Emit Flammable Gases (Water-reactive Substances)

General

 Substances are included in Class 4 if they are flammable solids, substances liable to spontaneous combustion or substances that on contact with water emit flammable gases (water-reactive substances) and meet the criteria for inclusion in one of the divisions and packing groups of Class 4.

Divisions

  •  (1) Class 4 has three divisions:

    • (a) Class 4.1, Flammable Solids, which consists of substances that are

      • (i) readily combustible, as determined in accordance with section 2.4.2.2 of Chapter 2.4 of the UN Recommendations,

      • (ii) under normal conditions of transport, liable to cause fire through friction,

      • (iii) solid desensitized explosives, which are solid explosives desensitized through wetting with water or alcohols or diluted with other substances to form a homogeneous solid mixture to suppress their explosive properties so that they are not included in Class 1, Explosives,

      • (iv) self-reactive substances that are liable to undergo a strongly exothermic decomposition even without the participation of oxygen (air), as determined in accordance with section 2.4.2.3 of Chapter 2.4 of the UN Recommendations, but Class 4.1 does not include substances that have

        • (A) a primary class of Class 1, Explosives, Class 5.1, Oxidizing Substances, or Class 5.2, Organic Peroxides,

        • (B) a heat of decomposition less than 300 J/g, or

        • (C) a self-accelerating decomposition temperature (SADT) that is greater than 75°C for a 50 kg means of containment, as determined in accordance with section 2.4.2.3.4 of Chapter 2.4 of the UN Recommendations,

      • (iv.1) polymerizing substances that, without stabilization, are liable to undergo a strongly exothermic reaction resulting in the formation of larger molecules or resulting in the formation of polymers under conditions normally encountered in transport,

      • (v) identified by one of the following UN numbers: UN2956, UN3241, UN3242 or UN3251, or

      • (vi) are in the list of currently assigned self-reactive substances in section 2.4.2.3.2.3 of Chapter 2.4 of the UN Recommendations;

    • (b) Class 4.2, Substances Liable to Spontaneous Combustion, which consists of

      • (i) pyrophoric substances that spontaneously ignite within 5 minutes after coming into contact with air, as determined in accordance with section 2.4.3.2 of Chapter 2.4 of the UN Recommendations, and

      • (ii) self-heating substances that, when in large amounts (kilograms), spontaneously ignite on contact with air after long periods (hours or days), as determined in accordance with section 2.4.3.2 of Chapter 2.4 of the UN Recommendations; and

    • (c) Class 4.3, Water-reactive Substances, which consists of substances that, in tests performed in accordance with section 2.4.4.2 of Chapter 2.4 of the UN Recommendations, emit a flammable gas at a rate greater than 1 L/kg of substance per hour or spontaneously ignite at any step in the test procedure.

  • (2) For the purposes of subparagraph (1)(a)(iv.1), a substance is considered to be a polymerizing substance of Class 4.1 if it

    • (a) has a self-accelerating polymerization temperature (SAPT) that is less than or equal to 75°C under the conditions in which the substance or mixture is to be transported, with or without chemical stabilization as offered for transport, and in the means of containment in which the substance or mixture is to be transported;

    • (b) exhibits a heat of reaction of more than 300 J/g; and

    • (c) does not meet any other criteria for inclusion in Classes 1 to 8.

  • SOR/2017-137, s. 20

Polymerizing Substances

 A person must not offer for transport, handle or transport the following polymerizing substances unless they are stabilized by temperature control:

  • (a) polymerizing substance that is in a small means of containment prescribed by TP 14850 or Chapter 6.1 of the UN Recommendations or in an intermediate bulk container (IBC) and whose self-accelerating polymerization temperature (SAPT) is 50°C or less in the small means of containment or IBC; and

  • (b) a polymerizing substance that is in a large means of containment that is not an IBC and whose SAPT is 45°C or less in the large means of containment.

  • SOR/2017-137, s. 21

Packing Groups

  •  (1) Substances included in Class 4.1, Flammable Solids, are included in one of the following packing groups:

    • (a) Packing Group I, if the substances meet the criterion in subparagraph 2.21(1)(a)(iii), except that substances that have one of the following UN numbers are included in Packing Group II: UN2555, UN2556, UN2557, UN2907, UN3270, UN3319 or UN3344;

    • (b) Packing Group II, if

      • (i) the substances meet the criteria for inclusion in Class 4.1 in subparagraph 2.21(1)(a)(iv) or (v), except that substances that have one of the following UN numbers are included in Packing Group III: UN2956, UN3241 or UN3251,

      • (ii) in tests referred to in section 33.2.1 of Part III of the Manual of Tests and Criteria for readily combustible solids, excluding metal powders, the burning time of the substances is less than 45 seconds and the flame passes the wetted zone, or

      • (iii) in tests referred to in section 33.2.1 of Part III of the Manual of Tests and Criteria, for readily combustible solids that are powders of metals or metal alloys, the zone of reaction of the substances spreads over the whole length of the sample in 5 minutes or less; or

    • (c) Packing Group III, if

      • (i) in tests referred to in section 33.2.1 of Part III of the Manual of Tests and Criteria, for readily combustible solids, excluding metal powders, the burning time of the substances is less than 45 seconds and the wetted zone stops the flame propagation for at least 4 minutes,

      • (ii) in tests referred to in section 33.2.1 of Part III of the Manual of Tests and Criteria, for readily combustible solids that are powders of metals or metal alloys, the zone of reaction of the substances spreads over the whole length of the sample in more than 5 minutes but not more than 10 minutes, or

      • (iii) the substances are solids that are liable to cause fire through friction.

  • (2) Substances included in Class 4.2, Substances Liable to Spontaneous Combustion, are included in one of the following packing groups:

    • (a) Packing Group I, if the substances are pyrophoric solids or liquids;

    • (b) Packing Group II, if the substances are self-heating substances that give a positive result, as determined in accordance with section 2.4.3.2 of Chapter 2.4 of the UN Recommendations using a 25 mm sample cube at 140°C; or

    • (c) Packing Group III for all other substances.

  • (3) Substances included in Class 4.3, Water-reactive Substances, are included in one of the following packing groups:

    • (a) Packing Group I, if the substances

      • (i) react vigorously with water at ambient temperatures and demonstrate a tendency for the gas produced to ignite spontaneously, or

      • (ii) react readily with water at ambient temperatures so that the rate of evolution of flammable gas is greater than or equal to 10 L/kg of substance over any one minute;

    • (b) Packing Group II, if

      • (i) the substances react readily with water at ambient temperatures so that the rate of evolution of flammable gas is greater than or equal to 20 L/kg of substance per hour, and

      • (ii) the criteria for inclusion in Packing Group I are not met; or

    • (c) Packing Group III, if

      • (i) the substances react slowly with water at ambient temperatures so that the rate of evolution of flammable gas is greater than or equal to 1 L/kg of substance per hour, and

      • (ii) the criteria for inclusion in Packing Group I or II are not met.

  • SOR/2017-137, s. 22

Class 5, Oxidizing Substances and Organic Peroxides

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.

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

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

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

      • (A) they are liable to explosive decomposition,

      • (B) they burn rapidly,

      • (C) they are sensitive to impact or friction,

      • (D) they react dangerously with other substances, or

      • (E) they cause damage to the eyes, or

    • (iv) are in the list of currently assigned organic peroxides in section 2.5.3.2.4 of Chapter 2.5 of the UN Recommendations.

  • SOR/2017-137, s. 23(E)
 
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