The LWF Blog
Fire Safety for Healthcare Premises – External Fire Spread – Part 51December 6, 2018 12:54 pm
In LWF’s blog series for healthcare professionals, the aim is to give information on best practice of fire safety in hospitals and other healthcare premises. In part 50 of this series, we discussed the potential for external fire spread including calculating unprotected areas and consideration of the surfaces of external walls and roofs. In part 51, we continue looking at external fire spread, starting with junctions of different elements.
At the junction of wall and low-level roofs, there is an abutment where the roof must provide fire resistance to a minimum of 60 minutes (integrity and insulation) for a distance of 3 metres from the wall, unless sprinklers are installed throughout the area below the low-level roof.
In the case of a junction of compartment and sub-compartment walls and external walls, it may be that a compartment wall (or sub-compartment wall) meets an external wall, or that a protected shaft meets an external wall and in either case, a 1 metre wide storey-height strip of external wall with the same period of fire-resistance must be provided in order to prevent the potential for lateral fire spread.
Again, the provision of sprinklers on both sides of the compartment wall negates the requirement.
Where buildings or parts thereof are used for parking cars or other light vehicles, there is a necessity to depart from the measures undertaken to restrict fire within buildings. The reasons for this are that the fire load is easily defined and where the car park is well-ventilated there is a low probability of fire spreading from one storey to the next. In the case of car parks which are not open-sided, fewer concessions can be made.
The additional measures which should be taken relate to three specific ventilation methods – open-sided (high natural ventilation), natural ventilation and mechanical ventilation (seen in enclosed car parks).
In all car parks, access from the car park to the healthcare building should be via a protected lobby, or in the case of vertical access from the car park to the building, any stairways should be provided with protected lobbies which serve the car park storeys and provide access to one storey only of the building.
In part 52 of this series, LWF will continue looking at the requirements for car parks with what is necessary for open-sided car parks. 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 020 8668 8663.
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.