EN 14470-1

Flammable liquids - such as solvents, lubricants and paints - are widely used in practice. Under certain conditions, however, they may form flammable mixtures with the air. Strictly speaking, it is not the liquid itself that is dangerous, but the gases and vapours emitted by it. If the flash point is reached with external heat, it can lead to serious consequences. Judging from the danger potential, it would be almost irresponsible to store flammable liquids without any protection at the workplace. In work area in particular, the risk must be minimised. The European Standard describes the design and test criteria for safety cabinets used for the storage of flammable liquids in closed containers at normal room temperature and includes three main safety requirements: minimising the risk of fire and protecting the contents of the cabinet in case of fire for a known (tested) minimum period of time (Fire resistance class) as well as the minimisation of vapours released into the working environment and the containment of possible leaks inside the cabinets.

In practice, the fire resistance class allows the user, taking into account the particular circumstances, to select a cabinet that gives the workforce ample time to leave the room, and gives the firefighters sufficient time to get into the building before passing through the stored combustible materials to prevent an uncontrollable fire.

EN 14470-1 divides safety cabinets into 4 classes according to their fire resistance. The class number - 15, 30, 60 and 90 - represents the duration in minutes that the safety cabinet must at least withstand in case of fire. In many European countries, safety cabinets with a fire resistance of 90 minutes are state-of-the-art. For example, German regulations such as the TRGS 510 demand the highest fire resistance for the unrestricted storage of flammable liquids in workrooms. The TRGS 510 also defines safety cabinets in the sense of these TRGS bearings and with a fire resistance of at least 90 minutes as a storage section. On the other hand, safety cabinets classified as Type 30 may only be used under certain conditions. Type 15 safety cabinets are not allowed in Germany at all. In principle, the minimum requirements in the respective European countries must always be observed. Furthermore, the result of the risk assessment of the responsible persons in the enterprises is decisive for the choice of necessary fire resistance class.

If a safety cabinet according to EN 14470-1 is marked with the type class, the manufacturer must ensure that the cabinet meets the design requirements of the standard and has fulfilled the fire resistance test stated in the test conditions. The fire resistance of the cabinet is determined by a type examination. During the load test, the cabinet is heated with a flame in a fire chamber according to the standard temperature curve according to EN 1363-1: 1999, 5.1.1 and the temperature rise inside the cabinet is measured. Depending on the time that elapses until the internal temperature at one of the specified measuring points is max. 180 K, the cabinet is classified as type 15, 30, 60 or 90. It is also tested whether the cabinet meets the other requirements of EN 14470-1. This includes:

• Self-closing doors: The cabinet doors must close automatically and completely from any position. The closing time from the time of triggering may not exceed 20 seconds. If a detent is installed, the doors must fully close at a temperature of 50 (+ 0 / -10) °C in the vicinity of the front of the cabinet.

• Self-closing vents: The specified openings for supply and extract air must close automatically when they are exposed to a temperature of 70 (+/- 10) °C.

• Interior load capacity: The shelves and pull-outs of the safety cabinet must be able to withstand the maximum load specified by the manufacturer during the duration of the fire.

• Functional spill pallet: For the retention of leaks, a bottom tray must be present below the lowest level. Their minimum collection volume must be 10% of all vessels stored in the cabinet, or at least 110% of the volume of the largest single container. The floor pan must still be fully functional after exposure to fire.