A firefighter’s helmet is an object that symbolically bears a lot of weight. In addition to having to resist intense heat and flames it represents courage. Of course.
A short survey was organised, that asked people what material they thought the afore mentioned helmet was made of.
“Steel”, was the surprising answer of a high percentage of interviewees.
Steel? But it is known to be both heavy and conductive, which actually makes it impractical for an application such as a firefighter’s helmet!
Yes but steel has this symbolic value of strength and resistance, whereas plastics are more often considered as cheap and inflammable.
Nevertheless, a Croatian company named PAB, specialising in security equipments, chose a plastics (namely a poly¬ether sulfone, or PESU) to manufacture the visor of its very heat-resistant, brand new firefighter’s helmet.
The firefighter’s helmet and its visor have to be able to resist a temperature of 250°C [482°F] for 30 minutes without being damaged. This protective gear even has to be able to withstand a temperature of 1000°C [1832°F] for ten seconds.
Along with its high temperature resistance, this specific variant of PESU called Ultrason has an inherent fire safety (that is to say, fire safety without the addition of flame retardants). The toughness of this transparent plastic makes it very break-resistant, even under extremely rough conditions. The helmet and the visor can be efficiently produced by means of injection molding, so that even complex shapes with integrated functions can be easily achieved. The helmet weighs a mere 1.2 kg, which makes it very comfortable to wear.