Control of Major Accident Hazards Regulations (Northern Ireland) 2000

3.  ‘Flammable’, ‘highly flammable’, and ‘extremely flammable’ in categories 6, 7 and 8 mean:

(a) flammable liquids—

substances and preparations having a flash point equal to or greater than 21°C and less than or equal to 55°C (risk phrase R10), supporting combustion;

(b) highly flammable liquids—

• substances and preparations which may become hot and finally catch fire in contact with air at ambient temperature without any input of energy (risk phrase R17),

• substances which have a flash point lower than 55°C and which remain liquid under pressure, where particular processing conditions, such as high pressure or high temperature, may create major accident hazards;

(ii) substances and preparations having a flash point lower than 21°C and which are not extremely flammable (risk phrase R11, second indent);

(c) extremely flammable gases and liquids—

(i) liquid substances and preparations which have a flash point lower than 0°C and the boiling point (or, in the case of a boiling range, the initial boiling point) of which at normal pressure is less than or equal to 35°C (risk phrase R12, first indent),

(ii) gaseous substances and preparations which are flammable in contact with air at ambient temperature and pressure (risk phrase R12, second indent), whether or not kept in the gaseous or liquid state under pressure, excluding liquefied extremely flammable gases (including liquefied petroleum gas) and natural gas referred to in Part II, and

(iii) flammable liquid substances and preparations maintained at a temperature above their boiling point.