The principle of respiratory protection relies on creating a physical barrier between the user and the surrounding air. In most cases this is achieved with a hood or mask, where exchangeable filters form the separation between the environment and the inhaled air. This is a form of dependent respiratory protection — the user is dependent on the direct ambient air. In certain situations, however, such systems do not offer sufficient protection and independent respiratory protection must be chosen.
Independent respiratory protection
With independent respiratory protection, clean air is supplied from outside through air hoses. The term 'independent' refers to the fact that the user is independent of the ambient air. No matter how severe the air pollution, the user always inhales clean air, regardless of the concentration and nature of the harmful substances present. The clean air can be delivered to the user either via oxygen cylinders or via a compressed-air network.
Advantages of independent respiratory protection
This form of respiratory protection is characterised by its high level of protection. In certain critical applications — think of firefighting or rescue operations — independent respiratory protective equipment is invariably used. In such situations the user does not always know what kind of air pollution he or she will face, or whether enough oxygen will be present. Only the best possible protection is sufficient. The high level of protection comes at the cost of more limited freedom of movement. Oxygen cylinders worn on the back or a connection to a compressed-air hose restrict the user's mobility. It goes without saying that independent respiratory protection is more cumbersome and complex than the more common dependent variant. This type of respiratory protection is therefore usually only chosen in situations that demand the highest level of protection.
Industrial applications
In certain sectors, industrial activities generate large amounts of air pollution — think for example of chemical processes or powder coating. A compressed-air hood can provide an excellent respiratory protection solution in such cases. Arbin's VanderGrinten hood has been the favourite of many for heavily polluted environments for decades. An additional advantage over independent respiratory protection is that compressed-air hoods do not require periodic filter changes.