Preliminary results from recent waste fire-fighting tests have shown that use of a detergent and a particular fire-fighting technique can put out a fire in just a couple of minutes.
200 MRW exclusive
Various fire-fighting methods were applied to a 27-tonne waste plastics fire burning in the open with the following outcomes:
- water took 30-40 minutes to put out the fire (although it was not fully out)
- compressed air foam (CAF) took 10-20 minutes to put out the fire
- a detergent, called a Type A agent, along with a particular fire-fighting technique put out the fire in 2 minutes 27 seconds
The tests during October, focused on practical fire-fighting and extinguishing fires, were in the third phase of research by the Waste Industry Safety and Health (WISH) forum into waste fires, building on the knowledge gained during the first two phases. They were conducted at the Fire Service College at Moreton-in-Marsh, Gloucestershire.
WISH chair Chris Jones explained that the use of Type A detergent and the particular technique was as a result of knowledge gained during the second phase.
The phase two trials revealed that fire vortices drove the super-high temperatures experienced in waste fires. By aiming their jets at the base of a vortex, fire-fighters found that water was sucked into the vortex, extinguishing the fire.
Jones explained: “Providing the water does not form little droplets – which is where the [detergent] comes in – you just keep feeding it into the base of the vortex and the vortex does the rest for you. It distributes it evenly across the fire and takes out the heat, which knocks out the base of the fire triangle – and it goes out.”
According to a senior fire officer involved, this could mean that waste sites armed with a drum of the relevant material, a mixing valve and a team of people trained to use hoses could extinguish a blaze before the fire brigade arrived.
Jones added that “fabulous outcomes” had been achieved during the tests. The team now needed to work through the “terabytes and terabytes” of data gathered to analyse and explain the tactics, and understand why they worked.
They will also need to work out how to translate the findings into guidance.
But he warned the waste sector not to get “carried away” with the headline findings because during tests with fires contained in concrete bunkers – which are commonly used in the industry – the waste was still found to be alight underneath even when the flames had been extinguished. The fire-fighting, however, had removed the visible fire so that it was encapsulated, dramatically reducing the amount of smoke.
- MRW will be carrying an in-depth report on the latest trials and their findings in the January issue