Tips: What should be paid attention to when purchasing and checking helmets?

Helmets are one of the “building treasures” of nets, belts, and caps. They are also the most common special labor protection articles. They are widely used by mines, chemical industry, machinery, metallurgy, and other industries and play a major role in protecting the life safety of workers. . The extensive use of a large number of regular replacement, it will often involve procurement and acceptance.

Helmet purchase

In the production and business operation units, helmet purchases generally involve procurement departments such as materials or supply, administration, and security. The materials, protection functions, colors, structures, and styles of helmets vary, and they are not simply purchased in accordance with the number of standards issued. It. In order to purchase helmets that meet the needs of use, the procurement and implementation department must hope to purchase applicable helmets from many qualified suppliers according to the management system and procurement procedures to meet the operational requirements of front-line personnel.

1.1 cap shell material

The commonly used helmet caps are made of low-pressure polyethylene plastic (HDPE), acrylonitrile-1,3-butadiene-styrene plastic (ABS), glass fiber reinforced plastic (FRP), polycarbonate plastic (PC), polypropylene plastic (PP) and so on.

HDPE has high rigidity and toughness, good cold resistance, can maintain a certain toughness at low temperature, good resistance to environmental stress cracking, acid and alkali resistance, organic solvent resistance, excellent electrical insulation, and relatively low mechanical properties It is easy to deform, brittle, aging, suitable for metallurgy, petroleum, chemical industry, construction, mining, power, machinery, transportation, geology, forestry, etc., with low impact strength for indoor operations, and is the most widely used hard hat material. .

In ABS, A represents acrylonitrile, B represents butadiene, and S represents styrene. With the adjustment of the ratio of the three components, the physical properties of the resin will change. ABS has excellent impact strength, electrical properties, abrasion resistance in the environment of -25°C~60°C, resistant to inorganic salts, alkalis and acids, insoluble in most alcohols and hydrocarbon solvents, easily soluble in aldehydes, Ketones, esters and some chlorinated hydrocarbons, but its poor heat resistance and weather resistance, easy to produce degradation under the action of ultraviolet light, suitable for mining, machinery industry and other high-impact indoor room temperature, excellent comprehensive performance Its application is getting wider and wider.

FRP is a composite material made of glass or other fibers and its products (cloth, tape, felt, yarn, etc.) as a reinforcing material and synthetic resins such as unsaturated polyester, epoxy resin and phenolic resin as matrix materials, and has high strength. , Tensile strength close to carbon steel, resistant to general concentrations of acids, alkalis, salts and a variety of oil and solvent corrosion, good electrical properties, low thermal conductivity, thermal protection and good ablation resistance, high temperature resistant resin can be applied At higher temperatures, ultraviolet radiation also degrades its performance. It is suitable for high temperature metallurgy, oilfield drilling, forest harvesting, power supply lines, high-rise construction, and construction in cold regions. FRP and ABS and HDPE have their own characteristics, and they are widely used. Hard hat material.

PC is a polymer containing a carbonate group in the molecular chain, flame retardancy, insulation, wear resistance, high hardness, high impact strength, resistant to weak acid, weak base, neutral oil, intolerant to strong alkali, intolerant part Oil and solvent, not resistant to hydrolysis, not resistant to ultraviolet light, sensitive to notches, suitable for oil field drilling, forest harvesting, power supply lines, construction, live working and other places, with relatively little use.

PP has good heat resistance, and product products can be steam sterilized is its outstanding advantages. Poor cold resistance, low-temperature impact strength, corrosion resistance, resistance to various chemical agents, but not tolerant to low molecular weight aliphatic hydrocarbons, aromatic hydrocarbons, and chlorinated hydrocarbons, has a high dielectric constant with increasing temperature, excellent insulation, However, it has poor flame retardancy, is easy to burn, is sensitive to ultraviolet rays, and is more susceptible to the effects of light and oxygen aging. It is suitable for pharmaceuticals and organic solvent operations, but due to poor anti-aging properties, the amount is relatively small.

1.2 Protection Features

The protection function of the helmet is divided into basic technical performance, additional flame retardant performance, lateral rigidity, anti-static performance, electrical insulation performance, and low temperature resistance performance.

In areas where there may be objects falling, debris splashing, ramming impact, puncture, slamming and falling, etc., the basic technical performance safety helmet may be selected; when the operating environment may have short-term contact with the flame, short-time local contact High-temperature objects or places exposed to high temperatures and flammable substances, and optional flame-retardant safety helmets; When the working environment may be laterally squeezed, including places where landslides and landslides may occur, there are foreseeable overturned objects. Sites with low speed collisions, such as tunnels, mines, and optional lateral rigid helmets; when the operating environment is highly sensitive to static electricity, deflagration may occur, or discharge may not occur, such as precision instrument processing, petrochemicals, and coal mines. Mining and other industries, optional anti-static performance safety helmet; When the working environment may contact three-phase AC power below 400 V and live working, such as electric power industry, optional electrical insulation helmet; When the operating environment is low temperature and the ambient temperature is not Below -20 °C, such as cold storage, forestry, etc., optional low temperature helmet.

1.3 color

When there is insufficient lighting in the working environment, use brightly colored safety helmets. When the visibility of the working environment is low, use a helmet with a large color difference with the environment or add a reflective strip that meets the requirements on the helmet. At the same time, it fully considers the role of safety, physiology, and psychology in terms of color and association. For example, personnel entering hazardous areas use yellow, people in common areas use white, management personnel use blue, safety management personnel use red, and contractors use oranges. Colors, suppliers, visitors, trainees use other colors, etc. Different people use different color helmets.

1.4 style

When it is possible to splash water, splashed scum, sunlight, and strong light directly to the eyes, choose a large-border, big-tongue safety helmet. When the working environment is a narrow venue, choose a small-edged safety helmet. If there is a slight anti-water showering requirement, Small edge helmets are available with a crimped construction. When there are other hazards or special needs in the operating environment, additional eye-face protection devices, ear protection devices, active cooling devices, electric induction devices, neck protection devices, lighting devices, warning signs and other accessories can be provided to the supplier. The requirements can also be requested by the additional company LOGO, personnel or number information.

2. Hard hat acceptance

When hard hats are delivered on time, the departments for issuing labor protection supplies such as the administrative and supply departments generally verify the number, color, style, etc. of the helmets in accordance with the supply contracts or documents, and perform inspection and acceptance procedures for storage. In fact, in addition to the above-mentioned acceptance documents and contents, the arrival helmet and its packaging, marking, instructions for use, as well as the qualification documents and inspection reports provided by the supplier, can be used as an important basis for the acceptance of the helmet.

2.1 Qualification

Hard hats are special protective articles for labor, and production and sales should be subject to relevant licenses or certifications. Suppliers can check whether the suppliers have relevant qualification certificates and whether there are “QS” or “LA” signs on the caps. Among them, the 10 digits under the “LA” logo on the caps and shells are the safety symbol identification numbers. The first two digits are the year of certification, and the three or four digits are the provinces (municipalities), the autonomous regions' logos or country numbers (imported products), and five. Up to seven products are identified (safety cap is 101), and the last three are serial numbers. The website of the Special Labor Protection Products Safety Signs Management Center (http://) can verify the supplier’s qualification status, such as whether the actual certified person, the validity period, and the product's material and protective functions are consistent with the information provided. The most common is the fraudulent use of certificates or specifications, such as the certified product is "plastic, basic technical performance", but the supply is "glass reinforced plastic, anti-static performance", and the main production equipment of plastic safety helmet is injection molding equipment, glass steel safety helmet The production equipment is pressure forming equipment, which is quite different. At this time, the possibility of OEM is higher.

2.2 Goods

The safety helmet is composed of a cap shell, a cap liner, a chin strap, and related accessories. The cap shell and the cap liner are connected by plugging, riveting, bolting, hooking, splicing, and the like. When inspecting the goods, the parts are inspected first. Whether it is intact, whether the accessories are damaged, whether the chin strap and the sweatband on the forehead of the hat hoop are complete; secondly, check whether the assembly of the plug, rivet, bolt, hanger, and cymbal is firm, whether the string is tight, and whether the adjustment section is tightly clamped or not. Whether the protrusion between the inner side and the cap liner is covered with a cushion, etc.; again, check whether there is a vertical buffer distance between the top of the helmet cap liner and the inner surface of the cap shell, and the vertical buffer distance is not more than 50 mm (recommended in the head and the cap shell) The interval between the tops is greater than 25mm.) Whether the horizontal cushioning distance between each side of the cap liner and the cap shell is between (5~20)mm and the wearing height from the bottom edge of the cap hoop to the top of the head is (80~90)mm If conditions permit, check if the weight of the helmet exceeds 430g, and if the weight of the cold helmet exceeds 600g. If the price of the helmet is lower than the normal range of the market and the color of the shell is mottled and gray, there is a possibility that the safety helmet may be used in combination with recycled materials, and the safety helmet of the returned material will be difficult to guarantee its safety protection performance.

2.3 Identification and instructions

Check whether the helmet cap of each helmet is stamped, sewn, riveted, molded or injection-molded with GB2811-2007 standard number (imported product is no exception), manufacturer name, production date, product name (not The permanent signs that are limited to the helmets, if they have special technical performance, have permanent marks such as anti-static performance, electrical insulation performance, lateral rigidity, flame retardancy, and low temperature resistance.

Check whether the manufacturer's name, address, and contact information in the product description are consistent with the qualification document and inspection report, whether there is a qualified mark and the place where the product is applicable and inapplicable. If there is an attachment or spare part, whether there is a detailed description of the attachment or spare part.

Check whether the two important data in the product description are complete: the scope of the applicable head circumference, which is an important basis for the user to wear; the shelf life, which is the manufacturer's maximum useful life based on the product specific process, formula or historical experience, etc. Hard hats of different manufacturers may have different shelf life.

Check the relevant instructions for product use, whether there are instructions for adjustment, assembly, use, cleaning, disinfecting, maintenance, maintenance, storage, etc., whether there are relevant instructions for modification, instructions for coating paint, solvents, stickers on external surfaces. Whether there are relevant instructions for the discriminating condition, such as the invalidation of the valid use period, etc.

Check whether there are 3 statements in the product description: In order to give full play to the protection, the helmet must be adjusted according to the size of the head circumference when wearing the helmet, and fasten the chin strap; after the helmet undergoes severe impact, even if there is no obvious damage, Must be replaced; Any modification or replacement of helmet accessories, unless done as recommended by the manufacturer, poses a danger to the user.

2.4 Inspection Report

Every year, helmet manufacturers entrust third-party inspection agencies to carry out product type inspections or annual inspections of safety signs. Each batch of helmets will undergo factory inspections or batch inspections, and the management department will conduct regular or irregular inspections. The relevant inspection report can be used as an important reference for inspection.

At the time of inspection, we can pay attention to whether the product category, specification, model and qualification document on the inspection report are consistent, and we can also pay attention to several important parameters. The basic technical performance and low temperature resistant helmet (-20°C) impact absorption performance: the force value does not exceed 4900N , Puncture resistance performance: steel cone does not contact the head die, the cap shell without debris off, anti-static performance safety helmet surface resistivity is less than 109Ω, electrical insulation performance safety cap leakage current does not exceed 1.2mA, flame retardant performance hard hat continued burning time Not more than 5s, the cap shell does not burn through, the maximum deformation of the lateral rigid helmet does not exceed 40mm, the residual deformation does not exceed 15mm, and no fragments fall off.