The LWF Blog
Fire Engineering Design and Risk Assessment – Hazard Classifications – Part 16
October 12, 2017 2:27 pmIn LWF’s fire engineering and risk assessment blog series for architects and those working in the business of building design, we have been looking at hazard classification of risks in relation to sprinkler installations. In Part 15, the nature of high hazard risks was outlined along with the extreme consequences should a fire occur in a high hazard risk building. It was ascertained that sprinkler protection must be designed specifically for the risk. In Part 16, we will continue looking at high hazard risks and sprinkler solutions.
One sprinkler system, designed to protect high piled storage risks, is known as Early Suppression Fast Response (ESFR). An ESFR system comprises large capacity sprinkler heads with quick response elements and large amounts of water. This design means that the water is directed into the small area where a fire has initially been detected, which douses the early stages of the fire, before it can grow. The objective of the system is to extinguish the fire rather than suppressing it, which means that while the amount of water is significant, it is delivered quickly and so the duration of sprinkler activation is shorter than it would be in the case of a standard sprinkler configuration.
Two material storage situations fall outside the standard hazard classifications and so are worth a particular mention. The first is potable spirit storage. Where potable spirit is held in storage within a building, this must be taken into consideration as a part of the sprinkler system design. Such areas have separately identified storage types, design densities and assumed maximum area of operation (AMAO).
The second is oil and flammable liquid hazards. While it is possible to have certain types, or amounts of oil or other flammable liquid on the premises without a specific sprinkler design, it is true that each situation should be measured based on its own risk assessment.
Some methods of oil and flammable liquid storage or use might mean that a standard sprinkler configuration would not be sufficient protection if a fire were to start. For circumstances of high risk, a deluge type system with medium or high velocity spray heads might be necessary, or a system that delivers a foam mixture specifically designed to douse oil or chemical fires. In some situations, water mist systems may be more appropriate but the varied nature of potential solutions indicates the need to consider each risk on its own merits.
In Part 17 of this series, we will begin to discuss sprinkler heads and their operational characteristics. 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.