Welding Fumes and Gases
WELDING FUMES AND GASES
Welding produces metal fumes and gases that can make you sick. The risk depends on:
• The welding method (such as MIG, TIG, or stick).
• What the welding rod (electrode) is made of.
• Filler metals and base metals (such as mild steel and stainless steel).
• Paints and other coatings on the metals being welded.
In confined spaces, welding can be much more dangerous. With less fresh air, toxic fumes and gases can be much stronger. Shielding gases, like argon, displace the oxygen and kill you.
These are some of the hazards materials:
Stainless steel contains nickel and chromium. Nickel can cause asthma. Nickel and chromium can cause cancer. Chromium can cause sinus problems and “holes” between the nostrils.
Mild steel (red iron) and carbon steel contain manganese. Manganese can cause Parkinson’s disease, which cripples the nerves and muscles.
Zinc in galvanized metal or in paint (on welded surfaces) can cause metal fume fever. It feels like the flu and goes away in a few days after exposure ends.
COATINGS AND RESIDUES
Lead (in some paints) can cause lead poisoning headaches, sore muscles and joints, nausea, stomach cramps, irritability, memory loss, anemia, and kidney and nervous system damage. If lead dust goes home on work clothes/shoes, it can make your family sick, most of all your children.
Cadmium (in some paints and fillers) can cause kidney problems and cancer.
Welding through or near some solvents can produce phosgene, a poisonous gas. The gas can cause fluid in the lungs. You man not notice the problem until hours after you quit welding. But fluid in your lungs can kill you.
When carbon dioxide is used for shielding, carbon monoxide can form and kill you. The welding arc can form ozone and nitrous oxides from the air. MIG and TIG wielding make the most ozone, most of all when aluminum is welded. These fumes irritate the eyes, ear, nose, throat, and lungs and can damage the lungs
• Nitrous oxides can cause fluid in the lungs.
• OSHA says you must remove all paint and solvents before welding or torch cutting. Follow written instruction. Make sure all residues are removed.
• Use the safest welding method for the job. Stick welding makes much less fume than flux core welding.
• Use welding rods that produce a low fume. 90% of the fume can come from the rod. Welding guns that extract fumes can capture 95% of the fume.
• In a confined space, follow all the OSHA confined-space rules-like air monitoring, not storing torchesn the space, and ventilation.
• OSHA says you must have good ventilation. Use local-exhaust ventilation to remove fumes and gases at their source in still air. Keep the exhaust hood 4” to 6” from the fume source.
• Use air blowers to blow fumes away from you when you are outdoors and it’s windy.
• Keep your face far from the welding plume.
• If the ventilation is not good, use a respirator. If respirators are used, OSHA says your employer must have a full respiratory protection program. This means proper selection and fitting or respirators, medical screening to be sure a worker and wear a respirator, and worker training. Correct respirator storage and cleaning and an evaluation of the program are needed. If you smoke, quit.
OSHA has limits for exposure to metals, gases and total fumes during welding. But these limits may not protect you enough, because they are out of date. The National Institute for Occupational Safety and Health (NIOSH) welding fumes may cause cancer, so keep the fume levels as low as possible.