Storage and Minimum Separation Distances

For advice on flammability types and minimum separation distances for organic peroxides in relation to boundaries/buildings during storage and use, you should consult: The storage and handling of organic peroxides, Guidance Note CS21 which is produced by the Health & Safety Executive. Download your free copy here.

Flammability Types are categorised as follows:

Type 1 – This contains both ‘Explosive’ labelled packaged peroxides and packaged peroxides which burn very intensely.

Type 2 – This contains packaged peroxides which burn in a way which is intermediate between Types 1 and 3.

Type 3 – This contains packaged peroxides which burn in the range ‘gently’ up to something akin to solvents and hydrocarbons.

Type 4 – This contains packaged peroxides which are non-combustible and from which the available oxygen is not more than 5%.

In relation to this, the CS21 also provides advice on the storage of quantities up to specific amounts, by flammability type.

Pages 6 to 9 of CS21 cover:

  • Quantities up to 5 kg (Types 1 and 2) and up to 10 kg (Type 3)
  • Quantities up to 150 kg (Types 1 to 3)
  • Quantities over 150 kg
  • Minimum separation distances for detached stores holding more than 150kg of peroxides (Types 1 to 3)

The minimum separation distances from organic peroxides stores of Types 1, 2 and 3 packaged organic peroxides to boundaries and ‘sensitive facilities’ are shown in a table on page 10 of CS21 which shows the separation distance in metres from the centre of the store against the bunded storage area in square metres. See page 11 of the guidance for separation for organic peroxides supporting notes.

Why not read more about the safe labelling of organic peroxides, their storage or handling? Alternatively, check out our resources section which is updated regularly with news and advice on organic peroxides.