Super tough nylon cuts safety helmet weight

Edited by the Engineeringtalk editorial team Apr 28, 2005

The Procap respiratory protection helmet, designed to help protect workers in tough and hazardous environments, has three major parts made of Zytel SST nylon.

The Procap respiratory protection helmet, designed and manufactured by Scott Health and Safety of Finland to help protect workers in tough and hazardous environments, has three major parts made of Du Pont Zytel SST (stiff super tough) nylon.

The material was selected for its light weight, impact resistance and overall outstanding mechanical resistance at high and low temperatures.

Consisting of a helmet with built-in welding and industrial environment mask attachments, the Procap incorporates respiratory, head, face, eye and hearing protection systems as well as a host of other safety and ergonomic features.

The helmet includes a tough, heat and molten-metal resistant shell made of Zytel SST and an integrated welding shield and vision frame, also both made of the glass-reinforced super-tough nylon.

Facial protection is provided by a parallel rail system that supports the first-stage face protection shield and a second stage optional welding shield.

The two visors protect against heat, infra-red (IR) rays and welding, making the mask suitable for a wide range of industrial applications such as welding, metal processing, quarrying, foundry work and shipbuilding.

According to Scott Health and Safety, the Procap took two years to develop and perfect.

Its design was based on research carried out amongst shipyard and steel mill welders to see how it feels to wear protective helmets and masks, and where the current helmets could be improved.

"The major design challenge was to keep the helmet light and comfortable, yet tough".

"Not only the shell, but also critical smaller parts, such as screws and snap-fit elements, needed to be tough and durable", says design team spokesman Jyrki Jarvinen.

As an example of a critical small part made of Zytel SST, Jarvinen cited the triangular yellow roller pack for the welding and breathing mask: "We could use just one screw to keep both roller packs in place because of the strength of the yellow support in Zytel SST".

"The yellow roller pack is especially effective in guarding the unit against shocks at low temperatures - when welders emerge outside and fling their masks to the ground when taking their breaks, for example".

EU norms required Scott Health and Safety to submit Procap to a range of standard safety tests such as knock, drop, impact and shock resistance, which the helmet passed with flying colours.

Procap conforms to European (EN) norms as well as Australian safety norms; there are also plans for the US market, too.

The high marks gained by Zytel SST in all these impact tests at high and low temperatures meant that Scott Health and Safety could substantially reduce the weight of the helmet.

The integrated helmet and visors needed to resist high welding temperatures over long periods, which is why the nylon is reinforced with glass fibres.

The helmet also had to remain flexible in cold Scandinavian temperatures of -30C.

The helmet unit made of glass reinforced Zytel SST also displays much better chemical resistance than either polycarbonate or ABS, a material commonly used for such safety helmets.