The LWF Blog

Fire Safety for Healthcare Premises – High Risk Fire Hazards & Precautions – Part 91

September 2, 2019 12:59 pm

In LWF’s blog series for healthcare professionals, our aim is to give information on best practice of fire safety in hospitals and other healthcare premises. In part 90, we discussed the potential for corrosion in ductwork and how this should be avoided, and then considered the fire-fighting controls which should be present in a healthcare main kitchen. In part 91, LWF will talk about the ongoing maintenance of ventilation systems in healthcare venue main kitchens.

Necessary maintenance of ventilation systems for fire safety purposes

Ventilation systems in main kitchen environments require a high level of upkeep and maintenance. In particular, those systems which serve deep-fat fryers are a hidden hazard and it is necessary to pay particularly close attention to them in order to prevent fires starting and avoid fire spread if a fire starts.

Grease extraction filters by their nature attract grease which is a dangerous fuel for a potential fire. As they are used, grease extraction filters can become progressively greater fire hazards and must receive regular cleaning and inspections to ensure they are clean.

The planned maintenance system of the healthcare venue must include the internal cleaning of ductwork. In order to make the task less onerous, kitchen canopies are commercially available which contain self-cleaning/washing filters. This reduces the amount of manual cleaning and maintenance the filters require, but they will still require close attention and checking.

The maintenance programme should also include checking fan motors, fire dampers and all associated control devices are working correctly. Each element should be checked in accordance with the manufacturer’s instructions.

The Building Engineering Services Association produced two guides which are also useful:

TR 19 – Guide to Good practice: Internal cleanliness of ventilation systems
DW 172 – Specification for kitchen ventilation systems

The Loss Prevention Certification Board’s LPS1263: Requirements for the LPCB approval and listing of the fire performance of kitchen extract systems (PDF) should also be referred to.

The main fire hazard from hot cooking oils and fats comes from the overheating of oils and fats which can be caused by human error or inaccuracies in temperature-monitoring equipment. Safe cooking temperatures for fats are generally below 200 degrees Celsius with temperatures above that leading to flammable vapours and the potential for spontaneous ignition which occurs at over 310 degrees. Oil which has been previously used will take less time to reach flashpoint due to progressive oxidisation.

In part 92, LWF will look at the planning and location of the main kitchen in a healthcare venue. In the meantime, if you have any questions about this blog, or wish to discuss your own project with one of our fire engineers, please contact us.

Lawrence Webster Forrest has been working with their clients for over 25 years to produce innovative and exciting building projects. If you would like further information on how LWF and fire strategies could assist you, please contact Peter Gyere on 0800 410 1130.

While care has been taken to ensure that information contained in LWF’s publications is true and correct at the time of publication, changes in circumstances after the time of publication may impact on the accuracy of this information.