The Chief Fire Officers Association and others are investigating new methods to combat fires at waste recycling sites, estimated at one per day.
But we must turn our attention to what more can be done to prevent fires.
Semi-permanent buildings can be specially designed to cover waste, helping to decrease fire risks and lower insurance premiums.
The sheer number of waste storage fires has had a dramatic effect on insurance cover, with insurers pushing up premiums or declining to offer buildings, contents, machinery and business interruption cover. Yet De Boer has worked with loss adjusters following a number of fires, noting that they look favourably on waste storage with a protective covering.
Semi-permanent structures have a number of benefits over ‘bricks and mortar’ solutions because they can be erected swiftly, relocated to a future site and have a life span of up to 25 years. Temporary and semi-permanent structures are a robust solution, meeting stringent regulations, and are capable of being modified to operational needs.
The use of tensioned fabric as the cladding detail also offers a further cost-effective benefit. Many steel framed, steel clad buildings are damaged beyond repair in the event of a fire owing to the uncontrolled build-up of heat within the structure. Collapse of the building, typically when the fire is well established, leads to extensive structural damage.
By comparison, a tensioned fabric structure will allow the heat to escape, preventing damage to the structural steel frame. The ease and speed with which a fabric panel can be fitted means that day-to-day operations can be resumed quickly and efficiently, with minimal losses to the insurer.
Semi-permanent structures can also avoid dust traps, improve ventilation and include sprinkler systems and fire-resistant doors to further reduce fire risks.
Increasing ventilation can have a dramatic effect on the risk of waste fires. A simple roof canopy will shield recyclate and waste materials (which often includes highly combustible materials) from wet weather, preventing the absorption of moisture.
Green waste stored in piles is more likely to self-ignite if it soaks up moisture, which causes oxidation, thereby releasing energy and generating heat.
The heat trapped in waste material heaps is often unable to escape, raising the core temperature and causing spontaneous combustion. But open-sided roof canopies allow increased air movement through the storage facility, helping any moisture that might be present within the stored material to evaporate and reducing the risk of spontaneous combustion within the pile.
De Boer worked with Dudley Council to design a green waste storage facility that provided ventilation within the gable-end elevation, increasing the amount of air movement within the structure.
Waste storage barns can be fitted with sprinkler systems, which have an extremely high success rate of extinguishing fires. Professional systems are designed to match the fire load presented. This means that high-risk areas, such as waste management facilities, have a greater density of sprinkler heads.
Combustible dust is created during the handling process at large biomass stores such as the Liverpool Bulk Terminal (LBT) which can accommodate 65,000 tonnes of wood pellet. Fire hazards are dramatically increased with this dust-prone material, meaning that it is vital to reduce the amount that might be present in the free atmosphere.
Working with the LBT team, De Boer modified its All Weather Hall to include specialist circular hollow section steel within the frame and connecting details to eliminate dust traps. Using rounded profiles over square section steel helped to eliminate areas for dust to settle.
LBT was also offered the option of an internal liner membrane fastened to the structure to further limit the risk of dust collecting – this may be added at a later date.
This design input was vital to the client and its operational teams because a stray spark could trigger an explosive fire within a dust-laden atmosphere, meaning that the core requirements were to eliminate both dust and ignition sources.
To achieve this second requirement, the LBT was also fitted with fire-proof Atex-compliant roller shutter doors which are specifically designed for explosive atmospheres such as combustible dusts.
Many people are unaware of just how long-lasting a temporary structure can actually be and, ironically, just what lasting benefits they can offer the waste management sector as a solution to the risk of fire and spiralling insurance premiums.
Robert Alvarez is sales director, commercial, at De Boer