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Proposals to remove fourteen legislative measures

Table 2 Comparison of NIHHS, COMAH, Planning Regulations and SEVESO II Directive to identify any differences if Schedule 1 of NIHHS - 'List of Hazardous Substances' is revoked

Return to Annex 3

(The seven substances with a lower threshold in NIHHS than in COMAH but are covered by the planning legislation are highlighted in bold in column 2)

Dangerous SubstanceNIHHS (Part II) (tonnes)COMAH (tonnes)Seveso II (tonnes)Planning (Hazardous Substances Regulations (tonnes)
LPG held at pressure > 1.4 bar resolute 25 50 50 25
LPG under refrigeration at a pressure of 1.4 bar absolute or less 50 50 50 50
Phosgene 2 0.3 0.3 0.3
Chlorine 10 10 10 10
Hydrogen Fluoride 10 generic very toxic
5
Generic very toxic
5
generic very toxic
5
Sulphur trioxide 15 15 15 15
Acrylonitrile 20 generic toxic
50
generic toxic
50
20
Hydrogen Cyanide 20 generic very toxic
5
generic very toxic
5
generic very toxic
5
Carbon Disulphide 20 generic toxic
50
generic toxic
50
20
Sulphur Dioxide 20 generic toxic
50
generic toxic
50
20
Bromine 40 20 20 20
Ammonia 100 Anhydrous ammonia or solution with concentration C > 25%
generic toxic
50
Ammonia solutions 25%>C>10%
100
Anhydrous ammonia or solution with concentration C > 25%
generic toxic
50
Ammonia solutions 25%>C>10%
100
generic toxic
50
Hydrogen 2 5 5 2
Ethylene oxide 5 5 5 5
Propylene oxide 5 5 5 5
Butyl peroxyacetate 5 Not named. No harmonised classification. Not named. No harmonised classification. 5
Butyl peroxyisobutyrate 5 Not named. No harmonised classification. Not named. No harmonised classification. 5
Butyl peroxymaleate 5 Not named. No harmonised classification. Not named. No harmonised classification. 5
Butyl peroxy isopropyl carbonate 5 Not named. No harmonised classification. Not named. No harmonised classification. 5
Dibenzyl peroxydicarbonate 5 Not named. No harmonised classification. Not named. No harmonised classification. 5
2,2 Bis(tert Butylperoxy)butane 5 Not named. No harmonised classification. Not named. No harmonised classification. 5
1,1 Bis(tert Butylperoxy)cyclohexane 5 Not named. No harmonised classification. Not named. No harmonised classification. 5
Di-sec-Butyl peroxydicarbonate 5 Not named. No harmonised classification. Not named. No harmonised classification. 5
2,2 Dihydroperoxypropane 5 Not named. No harmonised classification. Not named. No harmonised classification. 5
Di n propyl peroxydicarbonate 5 Not named. No harmonised classification. Not named. No harmonised classification. 5
Methyl ethyl ketone peroxide 5 Not named. No harmonised classification. Not named. No harmonised classification. (nb > 60%)
5
Sodium chlorate 25 50
(generic oxidising)
50
(generic oxidising)
25
Cellulose nitrate (other than - see note on pg 6 of the Regs) 50 50
(generic explosive note 2(a))
5000
(generic highly flammable if < 12.6% nitrogen)
50
(generic explosive UN/ADR Division 1.4)
5000
(generic highly flammable if < 12.6% nitrogen)
50
(other than – see note on pg 5 of the Regs)
Ammonium nitrate – note, proposal is that the threshold requirement in NIHHS is transferred to the NAMOS Regulations. 150 350
(> 28% ammonium nitrate or solutions containing more than 90% ammonium nitrate)
1250
(fertilisers with nitrogen content due to AN > 28%)
350
(> 28% ammonium nitrate or solutions containing more than 90% ammonium nitrate)
1250
(fertilisers with nitrogen content due to AN > 28%)
Dependant on the grade of AN ranges are 5000, 1250, 350, 10,
Aqueous solutions containing more than 90 parts of weight of ammonium nitrate per 100 parts by weight of solution 500 350
(solutions containing more than 90% ammonium nitrate)
350
(solutions containing more than 90% ammonium nitrate)
2009 substance A3 350 te
Liquid oxygen 500 200 200 2009 substance A27 200te

Part II of NIHHS – Classes of Substances not specifically named in Part I

Nb. There is no direct read across between the definitions of flammable or explosive in Part II of Schedule 1 of NIHHS and Part 3 of Schedule 1 of COMAH. The figures quoted for COMAH below are therefore references to the likely nearest threshold.

The Notes are derived from Seveso II, so the thresholds can be taken to be the same under Seveso II although the references to the Notes will be different

Dangerous SubstanceNIHHS (Part II) (tonnes)COMAH (tonnes)Seveso II (tonnes)Planning (Hazardous Substances Regulations (tonnes)
1. Gas or any mixture of gases which is flammable in air and is held in the installation as a gas. 15 50 for natural gas, otherwise 10 if COMAH Schedule 1, Part 3, Note 3(c)(ii) is relevant. 50 for natural gas, otherwise 10 if Annex 1, Part 3, Note 3(c)(2) is relevant. 2009 substance A66 15 te
2. A substance or any mixture of substances which is flammable in air and is normally held in the installation above its boiling point (measured at 1 bar absolute) as a liquid or as a mixture of liquid and gas at a pressure of more than 1.4 bar absolute. 25 being the total quantity of substances above the boiling points whether held singly or in mixtures. 10 – if COMAH Schedule 1, Part 3, Note 3(c)(iii) is relevant. 10 – if Annex 1, Part 3, Note 3(c)(3) is relevant. 2009 substance A67 25 te
3. A liquefied gas or any mixture of liquefied gases, which is flammable in air, has a boiling point of less than 0 degrees (measured at 1 bar absolute) and is normally held in the installation under refrigeration or cooling at a pressure of 1.4 bar resolute or less. 50
being the total quantity of substances having boiling points below 0 degrees C whether held singly or in mixtures.
no equivalent for comparison Not named 2009 substance A19 50 te
4. A liquid or any mixture of liquids not included in items 1 to 3 above, which has a flash point of less than 21 degrees C. 10,000 5000 - highly flammable if COMAH Schedule 1, Part 3, Note 3(b)(ii) is relevant 5000 - highly flammable 1992 substance A71 10,000te
1999
Substance 32 5,000 te
2009 substance A36a)
2,500 te
And also the generic category B8
5,000 te