1.3 Safety in the Welding Environment
Many of the safety practices to be observed in the welding environment apply equally to all welding processes.
1.3.1 Designated Welding and Cutting Areas. All welding and cutting should be done in designated areas of the shop, if possible. These areas should be made safe for welding and cutting operations with concrete floors, arc filter screens, protective drapes or curtains, and fire extinguishers. No combustibles should be permitted anywhere near welding or cutting areas. They should be stored safely in a separate room. 1.3.2 Health Hazards As a part of instruction in welding, it is important to be familiar with, and to be able to recognize, conditions that may be hazardous to health. It is also important to remember that the best way to attack a hazard is to eliminate or control the conditions causing it. The oxyfuel gas flame is generally safe, but carbon monoxide (CO) can build up to dangerous levels in a poorly ventilated place. The use of carbon dioxide CO2 as an arc welding shielding gas can create a problem because the CO2 breaks down in the welding arc and forms carbon monoxide. Reducing furnaces may have carbon monoxide (CO) emissions. Such furnaces should be well-vented at both the charging end and the discharging end. When vacuum furnaces or welding chambers are used, the pump exhaust must be vented away from people. Inert gases are dangerous to use in confined spaces. Inert gases displace air and oxygen. Workers entering spaces that are filled with an inert gas must wear an air-supplied purifier or self-contained breathing equipment. |
Coatings on metals can give off hazardous fumes when the metal is heated. For many years, red lead paint was commonly used outdoors for metal finishing and protection. Lead oxide fumes caused by burning lead paint coatings can produce acute lead poisoning. Terne plate is a metallic lead coating and is dangerous when heated.
Cadmium plating is frequently used on small parts. Even at low levels, cadmium oxide fumes can produce a chronic health condition. At high levels, the fumes are very harmful to the lungs and liver.
Beryllium is toxic even in very small amounts. Therefore, any operation involving beryllium should be avoided. Follow all safety precautions from manufacturers and employers to prevent beryllium exposure. Cobalt should be handled with the same precautionary safety measures as beryllium. It is crucial that all written and verbal safety regulations that are associated with these hazardous materials be carefully followed. Thorium is also toxic.
When thoriated electrodes are sharpened on a grinding wheel, be sure to ventilate the area well or wear proper breathing equipment.
Silver brazing alloy fumes can be quite dangerous. Fluorides are common in fluxes. Fluoride fumes are harmful. Manganese dioxide is not too toxic, but it can cause trouble if ventilation is poor. Oil smoke is a problem. The aromatics produced can be dangerous. Figure 1-9 shows a table of safe limits for some welding fumes.
Gas tungsten arc welding of aluminum can produce ozone. Ozone gas is toxic and can cause severe lung damage. It is irritating and causes coughing. It is essential for the welding area to be well ventilated. When welding under toxic conditions, it is also advisable to wear an appropriate breathing apparatus. Equipment choice depends on the types of hazardous fumes involved. Refer to Heading 1.3.3.
Ionizing radiations markedly increase the possibility of eye cataracts. Even small amounts of ultraviolet radiation can generate ionization and accelerate cataracts. Workers who are operating welding equipment, as well as helpers and other people in the area, must take precautions at all times to prevent eye injury by wearing proper protective equipment. Ultraviolet rays are harmful to the welder's vision. Safety goggles with appropriate filter lenses will provide protection. Never fail to protect the eyes, skin, and respiratory system.
The fumes that result from welding, brazing, braze welding, or cutting metals that are coated with or contain zinc, chromium, lead, cadmium, and beryllium are toxic. Cadmium fumes can kill!! Fumes from fluxes containing fluorides or sodium cyanide compounds also can be toxic. Excellent ventilation is required when working with these toxic metals or fluxes. It may be necessary to supplement normal ventilation with an air-supplied breathing apparatus. An air-supplied breathing apparatus must be used when working in a confined space.
Note: Remember that air-purifying respirators are only designed to filter out dust, dirt, and metal particles. They will not protect against toxic fumes.
The American National Standard Z49.1, Safety in Welding, Cutting, and Allied Processes, which is published by the American Welding Society, suggests placing a notice similar to the one shown in Figure 1-10 on major equipment used in the oxyfuel gas process. Labels like those shown in Figure 1-11 and Figure 1-12 are required on all welding products containing hazardous materials.
Cadmium plating is frequently used on small parts. Even at low levels, cadmium oxide fumes can produce a chronic health condition. At high levels, the fumes are very harmful to the lungs and liver.
Beryllium is toxic even in very small amounts. Therefore, any operation involving beryllium should be avoided. Follow all safety precautions from manufacturers and employers to prevent beryllium exposure. Cobalt should be handled with the same precautionary safety measures as beryllium. It is crucial that all written and verbal safety regulations that are associated with these hazardous materials be carefully followed. Thorium is also toxic.
When thoriated electrodes are sharpened on a grinding wheel, be sure to ventilate the area well or wear proper breathing equipment.
Silver brazing alloy fumes can be quite dangerous. Fluorides are common in fluxes. Fluoride fumes are harmful. Manganese dioxide is not too toxic, but it can cause trouble if ventilation is poor. Oil smoke is a problem. The aromatics produced can be dangerous. Figure 1-9 shows a table of safe limits for some welding fumes.
Gas tungsten arc welding of aluminum can produce ozone. Ozone gas is toxic and can cause severe lung damage. It is irritating and causes coughing. It is essential for the welding area to be well ventilated. When welding under toxic conditions, it is also advisable to wear an appropriate breathing apparatus. Equipment choice depends on the types of hazardous fumes involved. Refer to Heading 1.3.3.
Ionizing radiations markedly increase the possibility of eye cataracts. Even small amounts of ultraviolet radiation can generate ionization and accelerate cataracts. Workers who are operating welding equipment, as well as helpers and other people in the area, must take precautions at all times to prevent eye injury by wearing proper protective equipment. Ultraviolet rays are harmful to the welder's vision. Safety goggles with appropriate filter lenses will provide protection. Never fail to protect the eyes, skin, and respiratory system.
The fumes that result from welding, brazing, braze welding, or cutting metals that are coated with or contain zinc, chromium, lead, cadmium, and beryllium are toxic. Cadmium fumes can kill!! Fumes from fluxes containing fluorides or sodium cyanide compounds also can be toxic. Excellent ventilation is required when working with these toxic metals or fluxes. It may be necessary to supplement normal ventilation with an air-supplied breathing apparatus. An air-supplied breathing apparatus must be used when working in a confined space.
Note: Remember that air-purifying respirators are only designed to filter out dust, dirt, and metal particles. They will not protect against toxic fumes.
The American National Standard Z49.1, Safety in Welding, Cutting, and Allied Processes, which is published by the American Welding Society, suggests placing a notice similar to the one shown in Figure 1-10 on major equipment used in the oxyfuel gas process. Labels like those shown in Figure 1-11 and Figure 1-12 are required on all welding products containing hazardous materials.