As advances in technology is bringing the changes in building structures, the challenges of wind driven high rise fires are increasing and so the risks to firefighters and building occupants. Hence, the traditional fire fighting strategies need to be changed in order to fight effectively with high rise fires and save the building occupants and firefighters.
FEMA-FIRE project is mainly focused on establishing these fire fighting strategies and cultivating science into fire service culture.
PPV
Source
Positive Pressure Ventilation is a tactic in which stairwell of building is pressurized by using specially designed fans. The main advantage of PPV is that it drives the smoke and heat away from stairwell so as to ease firefighter’s job.
The positive pressure achieved on the fire floor depends on various factors such as fan specification, fan orientation, number of fans, fan deployment strategies, etc. Hence, the research is being conducted focusing on these relevant parameters.
Wind Control Devices
This strategy reduces the severity of Blowtorch effect, which make the high rise fires extremely dangerous and has killed many civilians including firefighters.
Wind control devices cover the windows through which wind is entering into fire apartment so as to reduce the air flow into fire apartment.
It ultimately stops the spread of fire (heat) and smoke into other rooms and public hallway.
During fire tests on Governor’s Island, it has been found that deployment of wind control devices drops the temperature by significant percentage and reduces heat, toxic gases which are dangerous for firefighters.
Research also is focused on increasing the effectiveness of these devices and ultimately reducing the blowtorch effect.
Two types of wind control devices are being used for this purpose as shown above:
High Rise Nozzle
In this strategy, water streams are deployed into fire apartment using high rise nozzles from outside safe vantage point which suppresses the fire. Currently two techniques are being used to deploy the water stream and are shown above:
Research is focused on the analysis and design of nozzles, cone spread, velocity of water stream, distance, deploying strategies and other relevant parameters including tests of nozzles.
