Industrial Protective Equipment

INDUSTRIAL PROTECTIVE EQUIPMENT, items worn by workers to protect against various industrial hazards and dangers. The nature of these items depends on the nature of the harmful exposure, namely: to protect against the effect of harmful substances on the skin and through the skin of the worker, as well as from certain types of industrial injuries - special clothing is used; for eye protection - goggles, shields, meshes; for protection of the respiratory organs - respirators; for protection of the hearing organs - devices that reduce sound conductivity, etc. The use of individual protective devices (due to a number of technical reasons) is associated with certain inconveniences for the wearer, and complete protection guarantee still does not exist in all cases. This is one of the main reasons why individual protective devices should be used only in cases where general and local technical and protective measures cannot completely protect the worker from industrial hazards. In-depth scientific work in the direction of standardization, determination of purpose, and rationalization of protective devices is being carried out both abroad and in the USSR (at the State Institute of Labor Protection) only recently and meets the long-standing need. Special clothing - items of dress that protect the worker's body and skin, as well as protect him from certain types of industrial injuries. Special clothing can either cover almost the entire body (combinations, suits, dresses, coats, cloaks) or serve only for local protection (aprons, sleeves, knee pads, footwear, gloves, headgear, gaiters, shields, etc.). The fabric and cut of special clothing must meet its main purpose without compromising hygiene, convenience, and durability. The following types of special clothing are distinguished depending on purpose. 1. Dust-proof clothing. It should not allow dust to pass through, be easy to clean, and retain its hygienic and protective properties after washing. 2. Clothing for hot shops. It is used for the following works. A. For work at high t°, but without direct contact with flame, sparks, splashes of molten metal or slag, and with hot metal (dryers, laundresses, workers in the yards of metallurgical and iron-smelting plants, etc.). The main requirements for the fabric of clothing in these cases are lightness, flexibility, and softness, which do not change after washing; good moisture absorption and moisture release, ability to be washed well. B. For work under the same conditions with simultaneous exposure to radiant energy to an extent that could cause burns on exposed or insufficiently protected skin (handlers of hot billets, turners and welders near furnaces, etc.), local protection against radiation is also necessary, achieved by applying local linings to the suit from loose, porous, unfinished woolen fabric. A peaked hat with wide brim serves to protect against radiant energy; long gloves - canvas with a felt palm or asbestos with a leather palm - provide maximum protection from heat. Footwear - felt or leather, closed in front. C. For work involving exposure to splashes of molten metal and hot solid particles (foundry workers of cast iron - 18

INDUSTRIAL PROTECTIVE EQUIPMENT

forgers, foundry workers, and brass workers in open-hearth shops, rollers and hook men in rolling mills, etc.). The main requirement: non-flammable fabric for the costume from the mentioned factors. G. With particularly strong action of the aforementioned factors, as well as with possible contact with hot metal and flame, depending on the nature of the work, special clothing made of asbestos fabric is added: for local protection - with constant wear, and for general - for short periods of work. 3. Clothing for protection from chemical hazards. Here the main requirement for fabrics - resistance to chemical agents and impermeability. But since such fabrics (rubber, rubber-impregnated, etc.) are also impermeable to air, they are used for general clothing only in extreme cases and temporarily. In particular, such clothing is used: A. For work with acids and acid salts. To protect the entire body, clothing made of dense woolen fabric, dyed black as a precaution, is used: acids form bright spots on such fabric, which serve as a warning to the worker, forcing him to immediately neutralize the acid with appropriate solutions always at hand. For protection in areas of greatest exposure, local special clothing made of rubber or rubberized fabric is used. B. When working with strong alkalis, clothing made of dense vegetable (preferably linen) fabric with a water-repellent impregnation that leaves pores open is used to protect the entire body. For local protection, rubber or rubberized fabric. C. For protection from oils and fats, local special clothing made of oiled (vulcanized) fabric is used. 4. Clothing for protection from water. A. For work associated with dampness and being drenched with water, general or local protection from waterproof but still porous fabrics is used. In dampness and cold, impregnated woolen fabrics are most suitable for general protection; with only dampness - impregnated linen canvas. Washing and rubbing significantly reduce the protective properties of these fabrics due to disruption of the mechanical bond between the fiber and the mineral salts coating it. Individual parts of the body subject to the greatest water exposure should be protected by clothing (aprons, sleeves, shields, etc.) from completely waterproof fabric with completely closed pores (rubber, rubber impregnation, etc.); this fabric is not as hygienic but is more reliable. Footwear, depending on the nature of water exposure, consists of waterproof boots (leather, rubber) or rubber galoshes. B. For work involving immersion in water, special clothing made of maximally waterproof fabric, cut to prevent water penetration, is used. The soles are protected by special leather 'pistons'. For complete immersion in water, diving suits made of the same fabric with a single opening at the collar are used. 5. Clothing for electrical work. As a general rule, work under current is prohibited. Special clothing (gloves and rubber galoshes) are worn in case of accidental contact with live parts of installations. Gloves are made of insulating material (usually rubber), non-hygroscopic, strong against tearing; a lining of soft, strong, non-hygroscopic material of white color (to make cracks visible) is mandatory. All seams must be carefully sealed. The length of gloves - not less than to the middle of the forearm. Galoshes - standard, certified, dielectric. Both gloves and galoshes, before being issued for use, must be tested under high voltages, 5,000-15,000 V, depending on their purpose, and subsequently must undergo control tests at intervals of 2-6 months. 6. Clothing for work near engines, transmissions, and machines. The danger of clothing being caught by moving machine parts is eliminated by using clothing and headgear without flapping or loose parts; the cut of the clothing - a combination. 7. Clothing for work involving friction of body parts against hard surfaces. Protection of the corresponding body parts is achieved by using strong, soft, and sufficiently thick devices (back protectors, shoulder pads, knee pads, etc.). Protective devices for eyes (goggles, shields, nets, helmets). Requirements for all protective goggles: for glass - strength, absence of bubbles, waviness, scratches, etc., parallelism of surfaces, same refractive coefficient in all parts of the glass (for colorless glass - light transparency not less than 80%), thickness not less than 2 mm; for frames - lightness, minimal narrowing of the field of vision (especially inward, downward, and outward), adaptation to the shape of the orbit and nose (tight fit, no pressure); frame material must be non-flammable, not deteriorate from industrial hazards, easily cleaned; parts adjacent to the face should conduct heat poorly, not irritate the skin, be easily cleaned; parts securing the glasses to the head should give them a stable position, not irritate the skin, and not press on the head. Depending on the nature of production, eye protective devices are divided into the following groups. 1. For protection from flying fragments and other solid particles that could injure the eye: A. Devices made of metal mesh (goggles, shields, masks). Their advantages - lightness, strength, free air exchange, no fogging; disadvantages - no protection against small particles, unpleasant sensation of mesh before the eyes, rapid heating in hot shops. B. Goggles with glasses and walls between the glass and the orbit - for protection from side fragments. 2. For protection from splashes of molten metal and slag. 3. For protection from non-toxic and non-corrosive dust, goggles with walls made of double fine metal mesh or knitwear are used; such goggles are convenient but provide insufficient protection. More reliable are goggles in a frame made of dust-impermeable material (metal), inserted into a leather half-mask. Ventilation holes, very small, are made on the side in the frame itself. 4. For protection from radiant energy, goggles with glasses that do not pass ultraviolet and infrared rays are used. This is determined by both the chemical composition of the glass and its color; both should vary depending on the nature of the rays to be blocked. Respirators. Respirators are divided into dust respirators and gas masks. Dust respirators can be 1) filtering and 2) hose-type. 1. Filtering respirators should provide minimal penetration of harmful substances and minimal resistance to breathing (according to German standards - not more than 6 mm of water column). Resistance increases with the thickness of the filter and decreases with its area. Fastening to the face is done either by mouthpieces with the nose held by a special clip (disadvantage - possible irritation of the gums from friction of the mouthpiece), or by half-masks (protection of mouth and nose) and masks (protection of the entire face and eyes). Masks and half-masks must fit tightly, not press on the skin, not irritate it, have minimal 'dead space' (accumulation of exhaled carbon dioxide), be made of light, non-flammable, and non-deteriorating material from industrial hazards; filters must be easily replaceable and cleanable. The following types of dust respirators exist. A. Respirators without valves. The continuous filtering surface has the form of a bandage that covers the mouth and nose or is stretched on a frame half-mask or is secured between two openwork layers of metal half-mask (Figure 1). Such respirators provide relatively little resistance but have the disadvantage that part of the exhaled air is trapped between the mask and the face. If the filter occupies only part of the respirator surface, this disadvantage is intensified and resistance is greater. B. Respirators with a detachable metal filter. Dust passes tortuously through a series of plates with differently arranged holes. These respirators have little resistance (mm H2O) but pass quite a lot of dust (up to 15%), so they are recommended only for non-toxic and non-corrosive types of heavy dust (Fig. 2). C. Respirators with inhalation and exhalation valves and a filter in the mask. D. Respirators with a large filter, attached to the body and connected to the mask by a corrugated rubber tube; such respirators allow combining maximum filter power with minimum resistance and are used against particularly toxic dust. 2. Hose-type respirators are applicable against very large amounts of dust that quickly clog the filter and consist

of a mask connected by a hose to a fan that creates an air flow through the filter. These respirators provide reliable protection but are cumbersome and limit mobility. Gas masks are used against toxic gases, vapors, and aerosols. They consist of a facepiece with a valve system and a filter cartridge that absorbs or neutralizes harmful substances. The effectiveness of gas masks depends on the type of filter used, which must be appropriate for the specific toxic substances present. Regular testing and replacement of filters are essential to maintain protection. Industrial protective equipment must be selected based on the specific hazards present in the workplace and should be properly maintained and inspected to ensure its effectiveness. Employers are responsible for providing appropriate protective equipment and training workers in its proper use.

Figure 2.

of a helmet, goggles, and hose. Clean air enters through the hose either by pressurization (bellows, compressor) or by being drawn in by the force of the lungs; the advantage of the hose is the absolute purity of the inhaled air, with pressurization providing complete absence of breathing resistance. The disadvantage is the limitation of the worker's field of movement, which is why hose respirators are only indicated for specific tasks (work at a sandblasting apparatus, cleaning paint drums and chambers, etc.). Gas masks. Main groups. A. Filtering, in which the worker inhales atmospheric air that has passed through an absorbent with a reagent. The duration of protection depends on the concentration of the poisonous gas. They are only permissible when there is sufficient oxygen in the surrounding air. B. Isolating - used when there is a lack of oxygen in the atmospheric air, as well as at high concentrations of harmful gas; for breathing, oxygen is supplied from special devices. C. Mixed (filter-isolating) - combining the properties of the previous types (see Gas masks). Devices for hearing protection are very few. Plugging the ears with cotton, wax, and gutta-percha plugs gives very questionable results. The so-called Eisel antiphones provide good protection against loud sounds (e.g., cannon fire), which consist of a hollow ebonite insert for the ear; the valve in the antiphone quite well allows ordinary sound waves to pass through, but during loud sounds it tightly seals the ear canal. However, in some individuals, unpleasant reflex phenomena occur when using this device, for example, nausea. Thick felt insoles in shoes also serve to protect the hearing organs from vibration.