1 Type and standard of helmet

At present, the helmets of domestic accessories stores are generally divided into: full helmet type safety helmet (full cover type), 3/4 safety helmet (open face type), half helmet type safety helmet (semi open face type) and faceless safety helmet (semi single type); According to the basic structure and shape, it can be divided into full helmet type and half helmet type.

Full helmet is a common motorcycle helmet, which can wrap the whole head of a person and protect the head from accidental impact. The helmet is generally made of AB S/PP engineering plastic materials, with a removable sponge lining, a quick insertion lock buckle, a full view PVC lens, and a vent hole on the helmet that can move up and down, Both left and right sides are provided with sliding plug-ins.

Half helmet helmets are similar to the helmets worn by workers. They are small in size and light in weight, and have better ventilation comfort than full helmets. The cushion foam layer filled in the helmets can be used to maintain the safety of the top of the head. Some half helmets are also equipped with goggles, which can be opened and closed at your discretion. Especially in summer, riding sunshades have better ventilation and lightweight advantages.

Now, there are different kinds of standards for all kinds of helmets on the market. Among them, "DOT" is the general road standard of the United States, "ECE R22-05" is the European Union safety standard, "+JIS" is the general road standard of Japan, "JIS T8133:2000" is the general road standard of Japan, and "SNELL M2000" is the higher recognized standard of internationally recognized racing cars.

The most common certifications of safety helmets are DOT, SNELL, JIS, SHARP, etc. Among them, DOT Department of Transportation is the U.S. certification, SHARP is the U.K. certification, Safety Helmet Assessment and Rating Program is the U.K. certification, JIS, Japanese Industrial Standards is the Japanese industrial standard, CSA is the Canadian certification, ECE/EN is certified in Europe, and A S/NZ is certified in Australia and New Zealand.

2 Internal structure of helmet

The helmet shell is usually made of glass fiber, because this kind of glass fiber belongs to a kind of high-quality anti-collision material. Now, most of the domestic helmets use this kind of glass fiber for the helmet shell of brand helmets whose quality meets the national standard. The whole structure is composed of shell, buffer layer, pad, wearing equipment, goggles, etc. Helmets are generally divided into small, medium, large and extra large ones, of which the size of large is 580~600 mm, the size of medium is 560~580 mm, and the size of small is 540~560 mm.