If your site stores or uses significant quantities of dangerous substances, you may be required by law to notify both the Fire and Rescue Service and the relevant enforcing authority.
The Dangerous Substances (Notification and Marking of Sites) Regulations 1990 (NAMOS) are designed to ensure firefighters attending an emergency are aware that dangerous substances may be present and can take appropriate precautions to protect people, property and the environment.
You must submit a notification if your site contains, or is expected to contain, 25 tonnes or more of dangerous substances at any one time.
Dangerous substances are classified under the Carriage of Dangerous Goods and Use of Transportable Pressure Equipment Regulations (CDG), which are based on the European Agreement concerning the International Carriage of Dangerous Goods by Road (ADR).
In addition, a separate notification requirement applies where a site stores 150 tonnes or more of relevant ammonium nitrate mixtures.
Relevant ammonium nitrate mixtures are defined as:
Ammonium nitrate, or mixtures containing ammonium nitrate, with a nitrogen content exceeding 15.75% by weight.
To help organisations meet their legal obligations, we have provided an online reporting form.
Please note that it is the responsibility of the site operator to determine whether the site meets the notification thresholds before submitting a notification.
Further guidance is available from the Health and Safety Executive (HSE): HSE Guidance INDG467
Under NAMOS, sites storing 25 tonnes or more of dangerous substances must display warning signs to alert attending firefighters to the presence of hazards.
These signs must be positioned at suitable access points to provide clear warning before emergency personnel enter the site.
Following notification, the Fire and Rescue Service may inspect the premises and advise on the number, type and location of signs required.
Where appropriate, additional signs may also be required within the site to identify specific areas containing significant hazards.
These markings help emergency responders quickly identify hazardous locations during an incident.
The person responsible for the site must notify the Fire and Rescue Service if any of the following occur:
Dangerous substances are no longer present on a permanent basis
The total quantity of dangerous substances falls permanently below 25 tonnes
The classifications of dangerous substances previously notified change
On 6 April 2013, the Notification of Installations Handling Hazardous Substances Regulations 1982 (NIHHS) were revoked.
As a result, the previous requirement to notify authorities when a site holds 150 tonnes or more of relevant ammonium nitrate mixtureswas transferred into the NAMOS Regulations. This simplified the regulatory framework by reducing duplication between notification systems.
For detailed guidance on dangerous substance classifications and your legal responsibilities, visit the Health and Safety Executive website:
Health and Safety Executive (HSE)
https://www.hse.gov.uk/pubns/indg467.htm
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