Head protection: safety helmet pressure principle and characteristics

A safety helmet is a protective device that prevents impact damage to the head. Consists of a cap shell, a cap liner, a lower cheek strap, and a rear hoop. The cap is hemispherical, solidified, lubricated and resilient, and the impact of the impact and the puncture kinetic energy are mainly accepted by the cap. A certain amount of space is left between the cap shell and the cap liner to cushion and disperse the instantaneous impact force and then prevent or reduce direct damage to the head. Impact absorption, puncture resistance, lateral rigidity, electrical insulation, and flame retardancy are requirements for the skill and function of the helmet.

Safety helmet pressure principle

The helmet can accept pressure mainly using three principles:

1. Buffer shock absorption effect: there is a gap of 25~50mm between the cap shell and the cap liner. When the object impacts the safety cap, the cap shell will not directly affect the top of the head due to the force deformation.

2. Dispersion stress effect: The cap shell is oval or hemispherical, and the appearance is lubricated. When the object is dropped on the cap shell, the object cannot stay and immediately fall off; and the cap shell is transferred to the surrounding by the accepted force of the impact point, passing through the cap cushioning The force of reduction can reach 2/3 or more. Other forces are transmitted to the skull of the person through the entire area of ​​the cap lining, so that the focus point is changed into a stress surface, and then the impact force is prevented from collecting at a certain point on the cap shell. , cut the force per unit area.

3. Biomechanics: It is necessary to be able to absorb 4900N in the national standard helmet. This is due to biological experiments, the maximum limit of human cervical spine when the force, beyond which the cervical spine will be damaged, the light leads to spasm, and the most serious life-threatening.

The hazards of low-priced hard hats:

Some low-priced hard hats are merely intangible and do not provide protection. In the selection of materials, the lining's planning foundation does not meet the requirements of the national standard. When the impact is received, it cannot be deformed in time and the stress is dispersed. If these products are selected, if there is an accidental attack at work, the head injury of the user will be indefinitely damaged, and the concussion will be formed in the light, and the life threatening will be serious.

Hard hat base features

Breathable outstanding light low risk safety helmet;

Good ventilation, light weight, providing the wearer with all comfort;

Protective effect of hard hat

When the head of the worker is impacted by a falling object, the helmet cap shell is used, and the cap liner is first divided into impact force across the entire area of ​​the cranium, and then the elastic deformation and plasticity of the buffer layout of various parts of the helmet are used. The deformed and promised layout damage absorbs most of the impact force, reducing the impact of the final effect to the person's head to less than 4900 N, and then serves to maintain the head of the worker. The information on the helmet shell cap has an important effect on the overall resistance of the helmet.

China Labor Insurance Network