In the course of our lives, almost all of us will have to address the question of head protection. Whether it is during our leisure activities or at work, a helmet helps to reduce or prevent head injuries.

However, only a helmet that is perfectly fitted to the individual shape and size of its wearer's head can provide maximum protection. However, Helmet manufacturers have had to work with the limited information about head measurements that was previously available. Above all, there was a shortage of information about head shapes.

Addressing the problem, the Hohenstein Institute has carried out a research project called Textile-based head protection systems, which makes detailed data about head shapes is available for the first time.

Head size and head shape

The researchers spent about two years measuring the heads of 6000 men, women and children, and thoroughly examining their shapes and dimensions. With the help of more than 40 defined measuring points, they analysed the circumference, width and length of the head and many other important dimensions, and evaluated them statistically.

This enabled them to develop a new sizing chart specifically for heads, to identify typical 3D head shapes and then work out the typical market share of each actual head shape among the population of Germany.

“Since people only wear head protection systems consistently if they are comfortable, getting the best possible fit is very important,” explained Simone Morlock, who was in charge of the project at the Hohenstein Institute.

Sizing charts and manufacturing

With her team, Simone Morlock has defined five main head types. These range from extremely round and round through normal and oval to extremely oval. To demonstrate these types, 3D models were developed which cover the whole spectrum of different head shapes of people living in Germany.

By using the sizing chart produced by the researchers for head sizes 48 to 64, which describes the dimensions of the head and face for the five head types, manufacturers can now offer a better range of sizes and product types.

The size-based presentation of head dimensions is a big help in industrial product development, because the sizing charts now show the actual dimensions for each size. The experts have also identified and described differences in the dimensions between age groups and between the genders.

Wearing characteristics and hygiene requirements

“To make sure that helmets not only fit as well as possible but also feel great to wear, we have studied the wearing comfort and hygiene requirements of textile-based head protection systems. This is because the materials that are used affect the climatic conditions under the helmet,” said Martin Harnisch. “For the first time, we also included the lining of the helmet in our examination.”

In the project, the textile lining of ski helmets was studied as an example. By using laboratory tests, it is easy to characterise the different helmet linings in terms of their heat and moisture management and how they feel on the skin (skin sensory functions).

For example, nearly all the lining materials took a long time to dry. Any potential ways of improving this were indicated. Unlike in previous studies, the scientists also took account of the hygienic properties of the head protection systems.

www.hohenstein.de