Dry goods | How much do you know about "hard hats"?


Release time:

2023-04-04

As an indispensable personal labor protection product, hard hats play the function of protecting the important head of the human body, and play an important role in safe production. Whether their quality is qualified or not is related to everyone in production.

As an indispensable personal labor protection product, safety helmet plays the function of protecting the important head of the human body, and plays an important role in safe production. Whether its quality is qualified or not is related to everyone in production.

Therefore, you must not be sloppy when purchasing safety helmets, and you must choose qualified and high-quality products. Whether it is the manufacturer, seller, quality inspection department of the helmet, or the enterprise responsible for the purchase, the construction team should be responsible for this and strictly control it to ensure the safety of front-line workers during operation.

In order to let everyone better understand and use helmets

Gaoma Safety Editor invites everyone to learn about safety helmets

Helmet impact test

As a protective product to prevent impact objects from hurting the head, safety helmets are mainly used in operations such as oil field drilling, forest logging, power supply lines, and building construction. Hard hats in different application fields are made of different materials, common ones are PP (polypropylene) hard hats, FRP (glass reinforced plastic) hard hats, PC (polycarbonate) plastic hard hats, ABS hard hats, miners hard hats, etc. Generally, it has the function of cushioning and shock absorption, and plays an important role in safe production.

A safety helmet manufacturer must obtain a production license to produce safety helmets. The manufacturer must produce according to national standards. It should be checked whether it holds a production license certificate and its validity period.
According to the new national standard GB2811-2019, under the three conditions of high temperature, low temperature and water immersion, the safety helmet with qualified quality shall be subjected to impact test by dropping a 5Kg steel hammer from a height of 1m. The impact force on the headform shall not exceed 4900N (1N=1kg·m/s², that is, the force required for an object with a mass of one kilogram to obtain an acceleration of 1m/s²); use a 3KG steel cone to drop the test from a height of 1m, the steel cone should not be in contact with the headform, and No fragments of the cap shall fall off.
Some construction sites will conduct helmet impact tests to check whether there is a problem with the helmets worn by workers that day.

A safety helmet is a protective product that prevents impact objects from hurting the head. Consists of hat shell, hat lining, chin strap and rear hoop. The cap shell is hemispherical, firm, smooth and elastic, and the impact and puncture kinetic energy of the striking object is mainly borne by the cap shell. There is a certain space between the cap shell and the cap liner, which can buffer and disperse the instantaneous impact force, so as to avoid or reduce the direct injury to the head. Impact absorption performance, puncture resistance performance, lateral rigidity, electrical insulation and flame retardancy are the basic technical performance requirements for safety helmets.

01. Features of hard hat

Lightweight, low-hazard hard hat with good ventilation.
Well ventilated and lightweight, it provides excellent comfort to the wearer.

02. The main structure of the helmet

Hat shell: bear the blow and separate the falling objects from the human body

Hat Hoop: Keeps the hard hat in a certain position on the head
Top Strap: Distributes impact and keeps the shell floated to disperse impact
Rear hoop: Locking device for head hoop
Chin Strap: Aids in maintaining helmet position and position
Sweatband: absorb sweat
Cushion pad: when impact occurs, reduce the impact force

03. Hard hat specifications

Vertical spacing: Measured according to the specified conditions, the value should be between 25-50mm.
Horizontal spacing: Measured according to the specified conditions, the value should be between 5-20mm.
Wearing height: Measured according to the specified conditions, the value should be between 80-90mm.
Hat hoop size: divided into the following three numbers:
Trumpet: 51-56cm
Medium size: 57-60cm
Large size: 61-64cm
Weight: The special type of helmet should not exceed 600g; the ordinary type of helmet should not exceed 430g; the relative error between the actual quality of the product and the marked quality should not exceed 5%.
Brim size: small 10mm, large 35mm. The inclination of the brim is preferably 20°-60°
Ventilation holes: ventilation holes can be set on both sides of the helmet
Visor: small 10mm, large 55mm
Color: The color of the helmet is generally light or eye-catching, such as white, light yellow, etc.

04. The main function of the helmet

The main purpose of wearing a safety helmet is to protect the head from injury. It can protect the head from injury or reduce the degree of head injury in the following situations:
1. When a falling object hits the head
2. When the operator falls from a height
3. When the head may get an electric shock
4. When walking or working in a low space, the head may collide with sharp and hard objects

05. Hard hat classification

Based on the purpose of use, safety helmet products are divided into two categories: general operation type (P type) safety helmet and special operation type (T type) safety helmet.
Among them, the T category is divided into five categories:
Category T1 applies to workplaces with fire sources
Type T2 is suitable for working places such as underground mines, tunnels, underground engineering, and logging
Class T3 is suitable for flammable and explosive workplaces

Therefore, before wearing the helmet, you should adjust the tightness of the helmet and fasten the chin strap, so that the helmet is fixed on the head and cannot move freely.

The chin strap is turned over the top of the hat, the chin strap is not fastened, the chin strap is put into the safety helmet, and the chin strap is not fastened... These are all wrong wearing methods. In addition to wearing a helmet incorrectly, it is also unsafe to use a damaged or expired helmet!

The following items should be paid attention to when using a safety helmet correctly:
1. Before wearing the safety helmet, adjust the rear adjustment belt to a suitable position according to your head shape, and then fasten the elastic belt inside the helmet. The tightness of the buffer pad is adjusted by the belt. The vertical distance between the top of the head and the top of the cap body is generally between 25 and 50mm, at least not less than 32mm. Only in this way can it be ensured that the cap body has enough space for buffering when subjected to an impact, and it is also conducive to the ventilation between the head and the cap body at ordinary times.
2. Don't wear the helmet crookedly, and don't wear the brim behind the head. Otherwise, the protective effect of the helmet against impact will be reduced.
3. The chin strap of the safety helmet must be buckled under the chin and fastened firmly, and the tightness should be moderate. This will prevent it from being blown off by the wind, or knocked off by other obstacles, or due to the head swinging back and forth, the helmet will fall off.
4. In addition to the cap lining installed inside the cap body, the top of the helmet body also has small holes for ventilation. But don't open holes casually for ventilation during use. Because doing so will reduce the strength of cap body.
5. Due to the use of the helmet, it will gradually be damaged. Therefore, it is necessary to check regularly to check whether there are cracks, dents, cracks and wear, etc. If any abnormalities are found, it should be replaced immediately, and no further use is allowed. Any hard hat that has been hit hard and has cracks, regardless of whether it is damaged or not, should be scrapped.
6. It is strictly forbidden to use a helmet with only the chin strap connected to the shell, and it is also a helmet without a buffer layer inside the cap.
7. Construction workers are not allowed to take off their safety helmets during on-site operations, put them aside, or use them as cushions.
8. Since most of the safety helmets are made of high-density and low-pressure polyethylene plastics, they have the properties of hardening and deterioration. So it is not easy to be exposed to the sun for a long time.
9. For new helmets, first check whether there is a certificate of production permission from the labor department and a product qualification certificate, and then check whether it is damaged, uneven in thickness, and whether the buffer layer, adjustment belt and elastic belt are complete and effective. Immediate replacement of non-compliance with specified requirements.
10. Helmets should also be worn when working indoors on site, especially when working indoors with live electricity, they must be worn carefully, because the helmet can not only prevent collisions, but also play an insulating role.
11. When using the safety helmet at ordinary times, it should be kept clean and tidy, and should not be in contact with fire sources, and should not be painted arbitrarily. If lost or damaged, it must be reissued or replaced immediately. No helmet is allowed to enter the construction site.
T4 (insulation) category is suitable for live working places
T5 (low temperature) category is suitable for low temperature working places

06. Specifications for the use of helmets

Hard hats are not adequate protection if they are not worn and used correctly.