09 February 2017
Safe storage is a key means of avoiding accidents when handling hazardous materials at work, but which method best protects staff, businesses and the environment in the event of fire? Sven Sievers advises.
IN MOST laboratories and industries the use of hazardous and combustible materials is part of the regular routine and is unavoidable. The improper storage of such materials puts people, the environment and property in great and constant danger. All it takes is a minor accident to occur in a laboratory or industrial premises, which causes a small fire to break out. Flammable materials incorrectly stored on a shelf quickly accelerate the spread of fire, reducing the time available to evacuate the premises and extinguish the fire. The result can be injury to people and damage to the premises.
So, the negligent handling and storage of hazardous materials has serious consequences. A general lack of safety measures, along with failure to mitigate the risk of fire spread, could lead to insurance issues. Additionally, the laboratory manager and safety manager could face prosecution, and the company’s senior managers may also be personally liable. Substantial costs for disposal and renovation would be incurred and incalculable production losses would ensue. Furthermore, the associated damage to the company´s reputation could have long-term effects.
Hazardous materials are therefore very much a big issue for every business. To avoid accidents and protect employees in the best possible way, hazardous materials must be stored correctly ‒ for example, in a safety storage cabinet. Strict regulations govern the handling and storage of hazardous materials: global regulations, such as GHS (globally harmonised system), EU directives and guidelines, as well as the rules and laws of individual countries all apply and must be observed. In this context, the most important standard is BS EN 14470-1:2004: Fire safety storage cabinets. Safety storage cabinets for flammable liquids.
Fire resistant cabinets
In modern laboratories, safety storage cabinets with a proven fire-resistance class in accordance with BS EN 14470-1 allow for safer local storage of toxic, flammable, or potentially explosive substances. They provide a series of safety measures that protect the stored hazardous materials against fire. First of all, in the event of fire, the drawers as well as the doors close automatically through thermal release. If a door open-arrest system isn’t used, the doors must close automatically from every position when released. The doors close at 122°F maximum (approximately 50°C) and the closing sequence is completed within 20 seconds – starting from any position. The automatic closing works on the basis of fusible links, which are located within the door open-arrest system, the ventilation spigots and the drawers. In the event of fire, the system ensures that all mechanisms close automatically.
Once the automatic drawer and door have closed, the air ducts will automatically shut. Following this, the gaps between the door and the frame of the safety storage cabinet become totally sealed through special intumescent-seal protection strips. When exposed to fire, these expand and seal hermetically to prevent heat from entering the cabinet.
The steel body and the insulation jointly prevent a critical temperature increase inside the cabinet. The steel body alone does not offer any protection; in fact, it is a strong heat conductor. Underneath the robust steel surface are multiple layers of fireproof mineral-fibre insulation material (calcium sulphate) and these prevent temperature increase within the cabinet.
The asecos safety storage cabinet, for example, can withstand a fire for up to 90 minutes. Temperatures may exceed 1,000°C but the containers used for storing flammable liquids and hazardous materials remain safe and perfectly intact, thus allowing sufficient time for personnel to evacuate the premises and firefighters to enter the building.
Cabinet or storeroom?
To ensure safe and legally-compliant storage of hazardous materials duty-holders must provide a storeroom, or use a safety storage cabinet with a minimum of 30 minutes´ fire resistance, up to a 90-minute maximum. Storerooms require plenty of space and are subject to specific building requirements. The storeroom walls, ceilings and doors must be manufactured from non-flammable building materials. When storing quantities of material up to 1,000kg, storerooms must be separated from adjacent rooms with fire-retardant protection. Wall and ceiling openings leading to adjacent rooms need to be secured against the spread of fire by means of suitable partitions, with corresponding fire resistance in the wall or ceiling containing the opening. Furthermore, storerooms must be designed as collection rooms, or be equipped with sumps.
All these requirements not only cost a lot of money but also impose restrictions on the company in terms of flexibility of use. Safety storage cabinets with 90 minutes´ fire resistance according to BS EN 14470-1 are also classified as a separate fire compartment. Therefore, a safety storage cabinet offers quick access to the required containers because the storage is clearly arranged and the cabinets are on the spot, so there is no need to transport hazardous materials from the storeroom to the workplace. For these reasons, hazardous materials in the workplace are generally stored in the safety storage cabinets when work is finished, so any potential accidents that might arise while transporting chemicals across site are avoided.
Sven Sievers is head of division product management and marketing at asecos GmbH
For more Information, visit www.asecos.co.uk