Analysis of results from the ‘phase 3’ waste fire tests, commissioned by the Waste Industry Safety and Health (WISH) Forum and conducted in autumn 2017, conclude that use of a non-standard wetting agent and alternative firefighting tactics, as well measures such as compartmentation and stack positioning, would reduce the severity of fire incidents at waste sites.
This knowledge is now entering the fire service’s operational guidance and will be introduced into WISH’s fire guidance.
The latest interim technical report, seen by MRW, was produced by International Fire Consultants and issued to WISH in September. WISH has produced a non-technical summary of the document, currently with Mark Andrews, national strategic lead for waste and recycling site fires at the National Fire Chiefs Council. He is due to have an approved, plain English version of this document ready for release in this month.
What works – or doesn’t
The IFC’s interim technical report issued in September included:
- Concrete walls and concrete blocks are an effective means of providing compartmentation, provided the joints are sealed
- Six-metre spacing between baled storage is not adequate and potentially dangerous in the case of plastic
- In general terms, wetting agent proved to be the most effective medium for extinguishing waste fires, while water proved to be the least effective
- Standard firefighting tactics are deemed to be ineffective and alternative operations should be considered when dealing with an incident of this type
- Proactive waste site management can reduce the severity of an incident through measures such as compartmentation and stack positioning
As MRW reported in January, the phase 3 tests yielded some remarkable outcomes. Use of a particular wetting agent and firefighting technique, whereby the wetting agent was aimed at the base of the fire vortex, resulted in a fire in bales of mixed plastic being extinguished in just two minutes.
Results and data from all the tests have been analysed, with interim reports produced along the way. A full scientific report on all findings is expected to be finished by the end of the year. It will then require peer review, which could take until mid-2019.
Chris Jones, WISH chair, says the organisation is “keen not to wait” for the completion of peer review before revising its waste fire guidance: “As soon as we have got a summary approved and had some more conversations with the Environment Agency (EA), we will look to review the WISH [Waste28] guidance, probably early next year.”
He adds that, as the phase 3 tests were primarily about firefighting, impact on the existing guidance will be limited. But he agrees that there are likely to be some recommendations.
“I can see that we might be recommending people having an intermediate bulk container (IBC) of a ‘type A’ wetting agent and a mixer valve on-site,” he says. “One of the questions we don’t know the answer to is whether or not putting a ‘type A’ agent into fixed systems will be beneficial. The type A agent used in the trials has to be deployed in a particular way to be effective: putting it into the base of the flames.
“Therefore putting it into sprinklers, for example, probably isn’t going to work but putting it into cannons might. There is some discussion about whether or not we need a ‘phase 4’ [set of tests] to examine that point, and there are a few other technical points.”
This specific wetting agent is not a standard component of firefighting kit, hence Jones’s point that major waste facilities may need to have their own IBC and valve for use. But this would require collaboration between the waste facility and the local fire authority because training exercises would be needed to ensure the fire service was familiar with the equipment and techniques required.
Within the fire service, Jones explains that an officer in each region will have the role of waste fires specialist, be aware of all the knowledge gained, and be the point of contact for advice.
The tests also confirmed that video heat and smoke detection technologies could detect deep-seated fires in piles composed of large particles, such as pre-crushed wood, because the large air spaces between the material allow hot air currents to escape and be detected. But with waste of smaller size particles, such as RDF, in a deep seated fire the air currents carrying the heat cannot get out, and are therefore undetectable by these technologies.
julia turner 400
Julia Turner, executive director, Wood Recyclers Association:
“The fire prevention plan (FPP) issue is still ongoing, but we are now very close to becoming the first material stream to publish sector-specific guidance to help wood recyclers and reprocessors gain an FPP for a standard permit.
“We are working with the Environment Agency (EA) on a list of acceptable alternative measures for operators who need more of a bespoke FPP, which allows them to move away from the initial guidance.
“Crucially, the EA has listened to our concerns about the guidance, and has been willing to work with us to find solutions that work for operators while achieving the EA’s main goals of protecting the public and the environment.”
Jones says: “In one of the tests in October 2017, we had a fire burning at 600°C for the best part of 36 hours, and it was completely invisible on the outside to both thermal and visual detection.”
He explains that strings of thermocouple sensors could be placed through waste piles. But the fire tests found that, particularly in self-heating fires, fire hotspots can ‘wander’ around the pile instead of being focused in the centre.
“Unless your thermocouple happens to be at the hotspot, you could have a hotspot wandering around inside your pile and you might never know. What that essentially says is that remote detection of a deep-seated fire is too hard. What you have to do is manage the piles and manage the waste storage so that they can’t happen.”
Another finding was that fire would climb up and over concrete bunker walls. Site operators therefore need to be aware of this and make adjustments to their sites. Aside from that, Jones said concrete bunkers proved “far more effective than we ever expected” and that, even with intense fires in bunkers, the outside wall would remain cool.
Noted in the technical report was the finding that using a simple fire-proof mastic sealer bought from a builder’s merchant was all that was needed to stop flames penetrating through the slight gaps found between blocks. This information, which can be implemented easily, is also likely to find its way into the revised guidance.
WISH is currently talking to the EA about the test outcomes, with the hope that the organisations can find a more unified position between the WISH guidance and EA Fire Prevention Plans.
Insurance for waste sites
Chris Jones, WISH chair:
“It continues to be extremely difficult to get property damage insurance for waste losses.
“We have been recommending that the insurance industry – which tends to brand all waste risks as being unacceptable and dangerous – needs to look much more closely at the individual sites. Some of the large insurers will not insure waste sites regardless of how good they are. We think that is short-sighted.
“The insurers have an opportunity to assist us in putting pressure on the poorer performing sites to comply. I am not saying that people who do not comply with WISH guidance should not get insurance. But those that do should be looked on differently – and some of the insurers are doing that.
“Two or three of them are actually supplying the WISH guidance and saying this is the standard that you really ought to be looking at before we come and talk to you.”
Jones says the discussions are at an early stage but are “promising”, with the opportunity to “have one consistent set of guidance from WISH and a regulatory position from EA”. Currently, WISH’s fire guidance is the regulatory guidance for Wales and Scotland but is notably not for England.
While WISH plans to update its waste fires guidance early in the new year, Jones says it is mindful of the changes because it is also used as regulatory guidance in other parts of the world, such as Australia, Canada and Sweden.
Publication of the final report and updated guidance next year will mark the culmination of some five years of research and testing into waste fires, costing the industry £250,000 in addition to countless hours of freely given time and equipment.
Jones says: “There is lots of new learning and what we need to do now is start to apply that.”