Separation distances

Every person who stores explosives at a site must ensure that the relevant separation distance is maintained.

There are some exceptions to having to maintain separation distances:

provided that the explosives are stored in a safe and suitable place, with all due precautions for public safety.  More information on storing such explosives safely can be found in the Overarching guidance – Safety provisions (L150).

Where the explosives listed above are being kept with small arms ammunition, any separation distance required due to the presence of small arms ammunition will continue to apply.

Some other stores will not be subject to the separation distance requirements of the regulations. They are stores:

Stores controlled by contractors on establishments owned or controlled by the Ministry of Defence are not exempt from the separation distance requirements.

Separation distances also apply to the storage of explosives even when a licence is not required and to stores operated by organisations which are exempt from the licensing requirements. This includes any stores operated by local authorities and police forces not detailed above.

*When they grant licences HSE and ONR will normally follow the distances given in Schedule 5 of ER2014 (or distances interpolated from these tables and the mathematical formulae which support them). HSE and ONR will normally follow the same approach to the aggregation hazard types and quantities of explosives required by Schedule 5. HSE and ONR may follow an alternative approach where it has been shown to provide an appropriate level of safety.

Buildings that are not normally occupied

Where the presence of people within a building on an explosives site is transient and that building would be a protected place of Class F, then for the purposes of applying separation distances, that building may be considered to be not normally occupied or unoccupied when it is being used by the people who are engaged in the site's explosives activities.

Examples of such unoccupied buildings could include toilets, changing rooms and switch-rooms. The requirements of regulation 26 of ER2014 would however mean that dutyholders will need to take account of the risks posed by such buildings in deciding where it might be appropriate to locate their stores and also have systems in place to ensure that appropriate measures have been taken to protect people using those facilities from the effects of a fire or explosion.

Buildings that are not on the explosives site and which are only occupied for a few minutes per day, such as:

should be treated as being occupied or inhabited and appropriate separation distances should be applied.

Further information

Updated: 2021-08-26