Fire-rated cabinets for chemicals explained

If you handle flammable substances in your business, both the HSE guidelines and your insurance company likely require you to have the correct fire-rated storage provision.

You must have highly flammable substances stored in a secured, safe location with the proper safety precautions.

The UK has a minimum requirement regulated by the HSE (Health & Safety Executive).

Fire-rated cabinets should provide a minimum of 30 minutes of fire resistance. The more excellent the resistance, the better, with 120 minutes being the best level of protection.

The Dangerous Substances and Explosive Atmospheres Regulations 2002 (DSEAR) ‘require risks from the indoor storage of dangerous substances to be controlled by elimination or by reducing the quantities of such substances in the workplace to a minimum and providing mitigation to protect against foreseeable incidents.’

Fire-rated cabinets are for storing quantities up to a maximum of 250 litres, dependent on the flashpoint temperature of the substance stored. If the flashpoint is below 37.8 °C, the limit is 50 litres.

The flashpoint refers to the temperature at which the chemical releases heavy vapours that are easily ignitable into the air.

The regulations recommend ‘that the maximum quantities that may be stored in cabinets and bins are no more than 50 litres for extremely, highly flammable and those flammable liquids with a flashpoint below the maximum ambient temperature of the workroom/working area; and no more than 250 litres for other flammable liquids with a higher flashpoint of up to 55°C.’

It is essential that, in the event of an incident, you can ensure that people can safely escape from a working area. This means that you need to have appropriately constructed storage cabinets that provide a physical barrier to delay the involvement of these materials in a fire and the passage of flame and hot gases to give sufficient time for the safe evacuation of people and the implementation of emergency procedures.

Fire-rated cabinets are for specific storage purposes.

I store quantities of explosive or highly flammable chemicals up to 250 litres. If the flashpoint is below 37.8 °C (a highly flammable liquid), the limit is 50 litres. The maximum storage capacity for a flashpoint of up to 55 °C is 250 litres.

HSE defines normal atmosphere conditions in DSEAR 2002 as between -20 °C and 40 °C and 0.8 to 1.1 bar.

The flashpoint refers to the temperature at which the chemical releases heavy vapours that are easily ignitable into the air.

Certain substances should be stored separately. Flammable liquids should not be stored with incompatible substances. The Storage of Packaged Dangerous Substances HSG717 guides the safe storage of incompatible chemicals and includes segregation recommendations. Read more on this here.

Combustible materials like packaging should not be kept in the flammable liquid store. Potentially, this could be the first material ignited, and a subsequent fire would likely compromise the safe storage of the flammable liquids containers.

For larger quantities of flammable substances, outdoor storage or a dedicated storage room should be in place.

The use of cabinets with enhanced fire performance should not be seen as a substitute for the provision of dedicated store rooms and outdoor storage areas for the safekeeping of containers which are nominally empty or are not needed for current work.

Fire-resistant or fire-rated cabinets should be located in a safe and suitable place. This means it should be as far away as possible from sources of ignition, busy areas, and processing areas and not obstruct any means of escape.

It is recommended that highly flammable liquids be stored in temperature-controlled environments away from areas of heavy foot traffic; the best practice is that this is an external storage unit located outdoors.

If you are storing quantities above 50 litres, the storage facility should be outdoors in a secure space. It should be marked and lockable.

These outdoor storage facilities must be situated away from occupied buildings, sources of ignition, and LPG tanks, away from or protected against the risk of impact to drains or underground areas, and away from boundaries. This reduces the risk of the severity of an incident escalating.

Outdoor storage rooms should have a fire rating of at least 60 minutes.

Consider a purpose-built internal store if you have more than 50 litres of flammable liquid to store but no outside space. Here, the same design considerations for an external store apply with the addition that, depending upon the quantities to be stored, a more extended fire resistance rating should be considered, e.g. 90 or 120 minutes.

DENIOS cabinets and storage rooms are built and tested to the highest possible standards. You will find a range of 60, 90, and 120-minute fire-rated available from us. Our team is happy to help you find the most appropriate solution.

See our fire-rated storage containers.

Look at our industry-leading lithium-ion battery storage rooms.