Hard hat is a permanent element of every construction worker's equipment. Due to the fact that it is made of a material resistant to mechanical damage and appropriate profiling, it protects the head against injuries that may be easily suffered at the construction site, underground, when unloading goods or working at heights. Hard hats are usually made of polypropylene and polyamide, they are also equipped with a regulated chinstrap. They should not only protect against falling and impact, but also electric shock. The obligation to wear a hard hat is regulated by health and safety provisions.