Hard hats: The "life helmet" for construction workers - A comprehensive interpretation of the selection and wearing standards of hard hats-1-1

Recently, a popular science article about construction safety protection has attracted attention. The hard hats, as the most basic and important personal protective equipment for construction workers, its correct selection and proper wearing directly affect the safety of every worker's life. According to the national standard "hard hats" (GB 2811), hard hats belong to special labor protection equipment and must obtain the special labor protection equipment safety mark (LA mark) before production, sales, and use.

Three styles, each with its own advantages

Currently, the mainstream hard hats on the market are classified into three types based on the shape of the brim: V-shaped hard hats have a wide field of vision and are suitable for general construction; Y-shaped hard hats have a large frontal protection area and are suitable for operations with a risk of falling from above; T-shaped hard hats provide all-round protection and are mostly used in complex operation environments such as tunnels and mines.

From the perspective of material, ABS plastic hard hats have good impact resistance and are suitable for general construction work; HDPP plastic hard hats are lightweight and have good weather resistance, often used in municipal and road projects; FRP fiberglass hard hats have high temperature resistance and corrosion resistance, widely used in high-risk industries such as metallurgy and chemical engineering; PC polycarbonate hard hats have both high strength and transparency, meeting the special requirements of head protection while also considering vision.

Selection tips: Four checks and one guarantee

Experts remind that when choosing a hard hats, the following points should be noted: It is necessary to select products with the LA safety mark and product certificate; Choose the appropriate helmet shell material and brim shape according to the working environment; Equip with adjustable and loose lower chin straps; The buffer space between the helmet liner and the helmet shell should be no less than 25 millimeters; The weight should not exceed 430 grams (for large-sized hard hats, the limit can be appropriately relaxed).

Correct wearing: Three steps to complete

Correctly wearing a hard hats requires following three steps: First, loosen the rear adjustment strap to the maximum and put it on your head; Second, adjust the rear strap to make the hard hats firmly fit your head, with a buffer gap of 25 to 50 millimeters between the helmet liner and the top of your head; Finally, tighten the lower chin strap, with the chin strap tightly against your chin and leaving a finger's width of looseness. After wearing, check if the helmet shell has any cracks or deformations, if the helmet liner is intact, and if the lower chin strap is firmly fastened.

It is particularly important to note that the chin strap must tightly fit the head circumference, and the chin strap must be tightened，strictly prohibit not wearing the chin strap or wearing it loosely；Strictly prohibit wearing the hard hats upside down or backward；Strictly prohibit placing towels， hats， or other items on the hard hats liner.

Technical indicators： Strict standards for safety

The technical indicators of hard hats are extremely strict. In terms of impact absorption performance， after being impacted by a 50-millimeter-diameter steel ball and a 5-kilogram falling hammer at a height of 1 meter， the force transmitted to the head mold should not exceed 4900 newtons； The requirements for puncture resistance are that after being impacted by a 3-kilogram steel cone and a 1-meter-height falling cone， it should not come into contact with the surface of the head mold； The lower chin strap and accessories must withstand a tensile force of 150 newtons without breaking or falling off； In terms of anti-static performance， the surface resistivity should not exceed 10⁹ ohms； The flame retardant performance requires that the flame burning time should not exceed 5 seconds， and the continuous burning time should not exceed 5 seconds； The thickness of the helmet shell should generally be no less than 2.5 millimeters.

In addition， for special working environments， there are also anti-static hard hats， insulated hard hats (able to withstand 1200 volts of alternating current)， cold-resistant hard hats (suitable for environments below -20 degrees Celsius)， and flame-retardant hard hats， etc.， as specialized products.

Service life： Plastic helmets not exceeding 2.5 years

hard hats also have a clear service life： plastic hard hats do not exceed 2.5 years， and FRP fiberglass hard hats do not exceed 3 years. hard hats beyond the expiration date are strictly prohibited from use. At the same time， if a hard hats is subjected to a significant impact， regardless of whether the appearance is damaged， it should be replaced immediately.

Entry inspection and daily checks： Guarding every step

When each batch of hard hats arrives, the LA safety mark, product certificate, and inspection report must be checked. The product model, production date, and validity period should also be verified. The appearance inspection requires that the helmet shell has no cracks, no obvious deformation, and no obvious color difference. The sample inspection quantity should be no less than 2% of the batch quantity and no less than 3 helmets.

Before daily work, workers should inspect the appearance of the hard hats. If any cracks, depressions, or perforations are found, they should be replaced immediately; check if the liner is intact and if the buffer space between the liner and the helmet shell is normal; check if the chin strap and its connecting parts are firm and if the adjustment is flexible.

Prohibition of use: These actions are not allowed

It is strictly prohibited to modify the hard hats by drilling, cutting, or heating; it is strictly prohibited to use the hard hats as a bucket, seat, or pad; it is strictly prohibited to store the hard hats in a high-temperature, sun-exposed, humid, or organic solvent environment.

Applicable processes: All personnel entering the site must wear hard hats

hard hats are essential protective equipment for all personnel entering the construction site, including managers, supervisors, and visitors. Typical process scenarios include: earthwork excavation and foundation construction, scaffolding erection and dismantling, formwork erection and dismantling, steel bar processing and binding, concrete pouring, lifting and hoisting operations, and decoration and renovation projects, etc.

Eight common hazards to be vigilant about

Experts have sorted out eight common safety hazards: not wearing the chin strap or wearing the chin strap loosely; using towels, cloth caps, etc. as padding inside the hard hats; wearing the hard hats askew or backward; using hard hats beyond their validity period; continuing to use the helmet with cracks or deformation in the helmet shell; using the hard hats as a container, pad, or seat; using substandard hard hats without LA safety mark or certificate; workers engaged in high-altitude operations not wearing the chin strap and wearing the helmet with the brim turned backward.

Safety is no trivial matter. A small hard hats carries the weight of life. Correct selection and proper wearing of hard hats is the most basic responsibility and commitment of every construction worker to themselves, their families, and their enterprises.