The potential hazards of welding include harmful smoke (a mixture of fine particles – fumes – of metal and toxic gases), intense heat and sparks, loud noises, bright light, ultraviolet and infrared radiation. Exposure to welding fumes has been a common problem for welders, especially for those involved in railroad track and shipyard welding, automobile industry, construction, and heavy equipment manufacturing. Welding fumes are internationally classified as carcinogenic to humans (IARC classification group 2B).
The composition of welding fumes depends on the type of metals and the kind of welding rods being used. If they are made of iron or steel, the main component of the fume will be iron oxide. Welding on plated, galvanized, and painted metals generates fumes with cadmium, zinc oxide, or lead. Depending on the composition of their coating, welding rods can also generate fluoride and silica. Stainless steel fumes will contain Chromium Oxide and Nickel Oxide that can cause asthma. For this reason, stainless steel welding fume is considered to be more harmful than mild steel fume.
Other toxic gases that are created during welding include Carbon Monoxide, Nitrogen Dioxides, Cadmium, and Ozone. If welding operations are being done in the presence of Chlorinated Hydrocarbons, hazardous concentrations of highly toxic Phosgene and Hydrogen Chloride may be produced.
If you cut a metal coated with paint that contains lead, welding fumes will contain Lead Oxide, which may cause lead poisoning that is harmful to your nervous system, kidneys, and reproductive system.
When galvanized steel is arc-welded, the heat of the welding arc vaporizes the zinc coating, because the boiling point of zinc is below the melting point of steel. Adverse health effects of exposure to welding fumes and gases include chronic and acute poisoning, metal fume fever, irritation of the respiratory tract, emphysema, pneumoconiosis, and other diseases.
In addition to health hazards of metal fumes and toxic gases, welding operations involve hazards of burns from flame, arc, molten metal, heated surfaces, and metal splatter. If arc welding is done near solvents containing Chlorinated Hydrocarbons, the ultraviolet light can react with the solvents to form Phosgene, a gas that is deadly in any amounts.
Personal Protective Equipment (PPE) should always be used along with, but never instead of, engineering controls and safe work practices. Proper eye shields, helmets, and a powered air respirator (PAPR) system can provide protection for your lungs, head, and eyes. With proper PPE the amount of gas and hazards welders are exposed to can be significantly reduced. These items include N95 respirators, flame-resistant gloves, safety glasses or goggles, welding helmets with appropriate filter lenses and plates, leather aprons, and long-sleeved welding jackets. Even if you wear a welding helmet with a filter plate to protect from arc rays and weld sparks, safety goggles can protect further against slag chips, grinding fragments and other hazards that can ricochet under the helmet. Welding helmet filter lenses and plates must meet the test for transmission of radiant energy prescribed in ANSI/ISEA Z87.1-2015, American National Standard for Occupational and Educational Personal Eye and Face Protection Devices. According to OSHA 29 CFR 1910.252 (b)(2)(ii)(B), “Helmets and hand shields shall be arranged to protect the face, neck, and ears from direct radiant heat from the arc.”
Flame-resistant pants or overalls and steel-toed shoes are also required. Many work sites need to have ventilation in addition to ANSI standard PPE for welders and workers in the area to stay safe. Ventilation equipment that meets UL specifications, such as a RamFan Blower with ducting that eliminates the presence of harmful fumes in the welding area. This will help prevent welders and other workers from breathing high levels of airborne contaminants and provide adequate breathing air. Adequate ventilation depends on a few factors:
Since welders work with highly toxic materials, lockers should be provided so work clothes can be stored separately from personal clothing.
40-50 welders are hospitalized every year with pneumonia caused by welding fumes, and 2 of these welders die. It is important to encourage welders to protect themselves and to report any respiratory health concerns to their managers and seek medical help in case of exposure.
If you have questions, please feel free to call us at 800-829-9580, or visit us online at www.pksafety.com.
The history of joining different metals together dates back to the Bronze Age. But it wasn’t until the end of the 19th century that the only welding process that existed was forge welding. Welding is a process that joins materials together by melting a metal piece with a filler metal to form a strong joint.
Today, the most common types of welding processes are:
Below is a table of safety hazards existing in different types of welding operations, and the recommendations on how to prevent injuries.
|TYPES OF HAZARDS||MPAW/PAC, Air Carbon Arc Processes||SMAW, GTAW, GMAW, FCAW||SAW||OXYFUEL||
|Ergonomic||Y||Y||Y||Y||Use proper lifting techniques, foot rest, knee pads, and take breaks, or frequently change position to prevent musculoskeletal injuries, minimize vibration, remove debris and clutter to avoid slips and falls|
|Electric Shock||Y||Y||Y||N||Inspect electrode holder for damage, do not touch electrically “hot” parts inside the welder case, keep welding cable and electrode holder insulation in perfect condition, use insulated tools, wear Arc Flash clothing, aprons, FR gloves, headwear and footwear.|
|Bright Light||Y||Y||Y||Y||Make sure you are wearing protective glasses with side shields, or a welding helmet with a dark lens.|
|UV Radiation||Y||Y||N||N||Wear UV protective clothing and headgear; the chart below indicates the correct lens shade numbers.|
|Toxic Fumes, Gases||Y||Y||N||Y||Do not weld in confined spaces without ventilation, stay upwind when welding outdoors; use respirators, portable exhaust systems: fans, fixed or removable exhaust hoods.|
|Fire, Burns, Heat||Y||Y||N||Y||Inspect work area, remove any flammable materials, ensure access to fire hoses, sand buckets, fire extinguishers, wear a welding helmet, FR cotton, FR leather work clothes, do not roll up sleeves, wear pants over the top of leather work boots with 6-to-8-inch ankle coverage and metatarsal guards over the shoe laces.|
|Noise||Y||Y||Y||Y||Define the appropriate hearing protection with the help of certified intrinsically safe sound meters. Use ear plugs or ear muffs in the environments with high levels of noise pollution.|
|Height (tower climbing)||Y||Y||N||Y||When working at heights, prevent falls by using Arc Flash harnesses and lanyards.|
|Welding Operation||Shade Number|
|Shielded Metal-Arc Welding using 1/16, 13/32, 1/8 and 5/32 inch diameter electrodes||10|
|Gas-Shielded Arc Welding (nonferrous) using 1/16, 3/32, 1/8 and 5/32 inch diameter electrodes||11|
|Gas-Shielded Arc Welding (ferrous) using 1/16, 3/32, 1/8 and 5/32 inch diameter electrodes||12|
|Shielded Metal Arc Welding using 3/16, 7/32, and 1/4 inch diameter electrodes||12|
|5/16, and 3/8 inch diameter electrodes||14|
|Atomic Hydrogen Welding||10-14|
|Torch Blazing||3 or 4|
|Light cutting, up to 1 in.||3 or 4|
|Medium cutting, 1-6 in.||4 or 5|
|Heavy cutting, over 6 in.||4 or 5|
|Light gas welding, up to 1/8 in.||4 or 5|
|Medium gas welding, 1/8-1/2 in.||5 or 6|
|Heavy gas welding, over 1/2 in.||6 or 8|
Sources of information: CCOHS.ca, OSHA.gov
If you have questions or need help finding the right protection equipment, please feel free to call us at 800-829-9580, or visit us online at www.pksafety.com.
Welders understand that the fumes and gases produced from their work can lead to serious illness. The danger and amount of exposure to the welders depend on the type of work being done, the rod, filler metals, base metals, coatings, contaminants, as well as the amount of ventilation and respiration protection.
We simply don’t know everything there is to know about protecting workers from welding fumes. However, there are some common precautions that can be taken to protect workers from injury and illness.
Welding fumes are basically a mixture of metallic oxides, fluorides, and silicates. Not so wonderful to be breathing into your lungs by themselves, but since we have to live and work in the real world, there are other considerations such as the paint, rust inhibitors, solvents, and other coatings on the welded metal which can create additional dangers.
With proper precaution, the amount of gas and vapor can be eliminated, or at least reduced to a high degree. Ventilation is always an essential control option. Whether you are ventilating the entire area or can drill down to a very specific confined space, replacing dirty air with clean is often the first go-to procedure. Many shops require ventilation that meets UL specifications such as the RamFan UB20 with ducting.
Another option is respiratory protection. Fumes produced by basic welding of iron or steel can often be blocked by wearing a simple N95 mask such as the 3M 8212 N95 Welding Particulate Respirator or as a step up, an N99 mask such as the Moldex Premium Disposable Welding Respirator. Both of these have exhalation valves to keep the mask cool. However, these types of disposable masks are only good for simple welding.
Once you start arc welding, the ozone created by the electrical arc produces fumes that require a more robust system of respiratory protection. Since the face shields worn to protect from infrared restrict the type of respirator and cartridge or filter that can be used, many welders prefer soft P100 filters like the 3M 2097 Particulate Mold Filter P100 because they have a layer of charcoal to absorb fumes and organic vapors and also can block far more of the particles carried on the air. The 2097s can be worn on the 3M 6000 Series half-face masks or the 3M 7500 Series which is made of soft silicon and is more comfortable when worn for long periods of time.
Even more sophisticated breathing systems exist. The Pureflo Welding Helmet is a powered air respirator with Shade 10 or Auto-darkening features, face, eyes, and head protection. But at a cost. Airline Respirators are also an option, but may not be appropriate for all worksites.
In the end, every site contains its own hazards, as well as the best solutions for keeping welders and other workers in the area safe. If you have questions about the best protection from welding fumes and gases, feel free to give us a call or visit us online at www.pksafety.com.
Check out our blog post on welding protection: WELDER SAFETY TIPS: HOW TO AVOID EXPOSURE TO WELDING HAZARDS.