How to mitigate the risk of kitchen fires

A substantial number of fires each year are caused in commercial (and domestic) kitchen environments. Due to the very nature of cooking, using heat, flame, and potentially flammable materials - particularly cooking oils - the fire risk is ever present, but the risks can be mitigated in a variety of ways.

The most common cause

The most common cause of commercial kitchen fires is overheating what is being cooked. This generally happens because of faulty or broken thermostats, using high temperatures beyond what is safe and because staff become distracted.

The more severe fire incidents are associated with poor housekeeping, particularly with regard to cleanliness and build up of combustible greases and fats around appliances and in hoods and ducting

Prevention is better than cure

Make sure all hygiene, health, and safety risk assessments - particularly the fire risk assessment - are completed so the risks in your particular kitchen are identified and the appropriate preventative measures implemented. It’s not just a paper exercise-  employees in the work area need to be made aware of the hazards identified, the control measures decided upon, and the procedures they need to follow.

Check that all workers are given the training they need to work safely, and a record held so that refreshers can be planned in as and when appropriate.

A safe system of work (SSOW) flowchart that sets out procedures to be followed for potentially hazardous tasks should be available to help staff.

• Don’t allow cooking equipment to be left unattended while it’s in use – busy workplaces and distractions can lead to a lack of attention that can lead to overheating and fire.
• Ideally provide the kitchen with an emergency shut-off button (to turn off gas and/or electrical supplies) but if you don’t have this feature, ensure all employees know where these can be safely turned off in the event of a fire. A sign detailing the cut off points is useful too.
• To contain any fire, kitchens should ideally be in rooms with fire-resisting construction wherever possible. 60 minutes’ fire-resistance is preferred (or longer if required under Building Regulations for your circumstances).
• Ductwork is a common means of rapid fire spread from kitchens to the rest of a building. You should only install fire-resistant ductwork (preferably either LPCB or FIRAS certified, if possible). There should be at least 50mm between combustible materials and extraction ducting.
• The build-up of grease and dust creates an extremely flammable medium for rapid fire spread so you should make sure kitchen equipment has enough space around it to be properly maintained and cleaned (and that the cleaning actually takes place regularly!).
• It’s a good idea to provide grease filtration systems that meet the requirements of LPS 1263 as well as replacing mesh-type grease-trap filters with flame barrier baffle type filters.
• Make sure grease and fume-extraction hoods, canopies, traps, and grease-filters are being cleaned at least weekly. Also, the fume-extraction system needs servicing at least every 12 months and deep-cleaned at least once every six months by a specialist contractor (or more frequently, if recommended by the contractor). Cleaning records and deep clean certificates should be kept. HVAC publication TR19 details the steps required for satisfactory cleaning as well as a guide to the required frequency based on the level of use of the kitchen.
• Make sure to have your kitchen and cooking equipment regularly inspected and maintained by a competent person. These inspections must include vital fire prevention elements such as thermostats and temperature controls.
• Cooking oil degrades over time and its auto ignition temperature drops accordingly, meaning the danger temperature gets ever closer to normal cooking temperatures, so you should change the cooking oil in deep-fat fryers regularly. Use guidance from your suppliers (including any discolouration charts) to help you with this.
• You should have a system in place for periodic inspections, testing and maintenance of your electrical appliances, including Portable Appliance Testing for items.
• The fixed electrical installation should be inspected and tested by a competent electrical contractor (e.g., NICEIC-approved or ECA member) as detailed in BS 7671, within the last five years – and importantly, any identified remedials actioned.
• Some larger kitchen equipment may be directly wired into the electrical supply via a spur instead of a plug – this is often excluded from ‘PAT’ testing as well as fixed electrical tests – it is important to ensure they still get checked.
• Where gas appliances are used annual safety checks by GasSAFE certified engineers should be carried out.
• Storage of combustibles such as cloths, oven gloves, cardboard packaging, etc should be such that they cannot get too close to flame or heat producing cooking equipment.

Kitchen Stove Guard

Some smaller kitchens in workplaces use domestic style cookers and these cookers are also present in student and other residential accommodation.  Kitchen fires can be the cause of up to almost half the annual fires in these premises, which are also associated with most fatalities (dwelling fires generally result in more fatalities each year than those in commercial premises).

Cookers can be fitted with equipment conforming to BS EN 50615:2015 “Household and similar electrical appliances. Safety. Particular requirements for devices for fire prevention and suppression for electric hobs (cooktops).” This equipment is intended to prevent fires by shutting off the cooker before a dangerous temperature is reached.

One example is the Firechief Kitchen Stove Guard, which is an EN 50615 compliant device that is intended to protect from fire in electric cookers as it measures the temperature from the stove top and gives a pre-alarm in case of a potentially dangerous situation. If the warning is not acknowledged, the Stove Guard alarms and cuts off the power to the cooker. When the cooker has cooled down to a safe temperature, it is ready to be used again.

The device works silently in the background and can also be used easily by special user groups. It adjusts its sensitivity level based on the kitchen and user’s cooking styles, so that false alarms do not disturb the cooking.

It acts before flames appear/are formed and prevents fires also when you are not present or are otherwise unable to switch the power off.

The product consists of a heat sensor, a control unit, and an installation kit.

Stove Guard’s intelligent and wireless heat sensor is attached underneath the cooker hood with adhesive and uses a button cell for power. The heat sensor can also be installed on the wall or the ceiling. The control unit is connected to the power supply of the cooker and installed out of sight

Measures for if a fire occurs

It is important that a kitchen has the correct equipment to deal with a fire, should it occur.

It is recommended that all commercial cooking and extraction equipment (including any associated extraction ductwork and hoods inside the building) are protected by having a fixed extinguishing system installed, in line with (or the equivalent of) LPS 1223. The system should include a local alarm, automatic activation by a detection system and manual activation – located a safe distance away from the cooking equipment, preferably by a fire escape route door. These systems use either a Wet Chemical solution or a fine Water Mist and whilst suitable for all kitchens, they are even more important where the exposed surface area of fryers exceeds 0.4sq.m. as this can beyond the capabilities of portable extinguishers (see BS5306-8).

As a back up to fixed systems and for other kitchen fires, portable extinguishers are required and must include those with the following properties:

• Be rated for both Class A (solids- cardboard, cloths, textiles, etc) fires and Class F (cooking oil) fires
• Be tested as safe near/on electrical equipment (The EN3-7 di-electric test)

This can be achieved using Water Mist or Wet Chemical extinguishers which fulfil both of the above. Your risk assessment may prefer a separate CO2 extinguisher for electrical equipment, but this is not effective and due to the pressure of discharge, potentially hazardous on cooking oils so staff training and signage should clearly identify which extinguisher is for which fire.

The correct extinguisher for Class F fires is determined by the maximum exposed surface area of open fryers and so you should take specialist advice as an extinguisher which is too small for the risk will be ineffective.

Small, contained fires in waste bins or cooking pans that are under 300mm diameter and contain less than 3 litres of oil can be effectively tackled by a fire blanket, as can clothing fires. Ensure your fire blankets are Kitemarked or LPCB approved to BS1869:2019 from a UK manufacturer (not just a UK supplier) as there are many fakes in circulation with no fire resistance. Where your blanket is for clothing as well as containers it should be at least 1.2m x 1.8m.

The building should have a suitable fire detection and warning system with a manual call point in the actual kitchen in addition to the usual locations and a written emergency procedure should be in place and practiced by having regular fire drills.

Fire Depot has been the UK's favourite fire safety supplier for over 50 years, we know the fire protection and prevention business inside out. Our experienced team can offer advice and guidance about any of our fire safety products. For expert help and advice, please contact the Fire Depot team on 0330 999 2233, email us at sales@firedepot.co.uk or visit https://www.firedepot.co.uk/ to see our full range of fire safety products.

The information contained within this blog is provided solely for general informational and educational purposes and is not intended as a substitute for professional advice. Before taking any actions based upon this information, we advise the reader to consult any and all relevant statutory or regulatory guidance and where felt necessary to consult a qualified fire or industry regulation professional. The use or reliance on any information contained herein is solely at the reader’s risk.