# The Control of Major Accident Hazards Regulations 1999, Part 3: Categories of Substances and Preparations not specifically named in Part 2


Column 1
Column 2
Column 3
Categories of dangerous substances
Quantity in tonnes
1 VERY TOXIC
5
20
2 TOXIC
50
200
3 OXIDISING
50
200
4 EXPLOSIVE (where the substance or preparation falls within the definition given in Note 2(a))
50
200
5 EXPLOSIVE (where the substance or preparation falls within the definition given in Note 2(b))
10
50
6 FLAMMABLE (where the substance or preparation falls within the definition given in Note 3(a))
5,000
50,000
7a HIGHLY FLAMMABLE (where the substance or preparation falls within the definition given in Note 3(b)(i))
50
200
7b HIGHLY FLAMMABLE liquids (where the substance or preparation falls within the definition given in Note 3(b)(ii))
5,000
50,000
8 EXTREMELY FLAMMABLE (where the substance or preparation falls within the definition given in Note 3(c))
10
50
9 DANGEROUS FOR THE ENVIRONMENT in combination with risk phrases:
(i) R50: “Very toxic to aquatic organisms”
200
500
(ii) R51: “Toxic to aquatic organisms”; and
R53: “May cause long-term adverse effects in the aquatic environment”
500
2,000
10 ANY CLASSIFICATION not covered by those given above in combination with risk phrases:
(i) R14: “Reacts violently with water” (including R14/15)
100
500
(ii) R29: “in contact with water, liberates toxic gas”
50
200

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Source: https://www.legislation.gov.uk/uksi/1999/743/schedule/1/part/3n2 (the official version)
Page: https://openlegislation.uk/control-of-major-accident-hazards-regulations-1999/schedule-1/part-3n2
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.