Welding Fume Exposure Health Effects – Acute and Chronic
Welders are subjected to a wide variety of health and safety risks and while performing their duties. It is recognized that injuries such as burns, cataracts and back problems are significant among welders.
Equally as important are the health risks of inhaling welding fumes.
Even if employers comply with the appropriate OSHA Permissible Exposure Limits (PELs), welding fume exposure can damage worker health, including both short term (acute) effects and long term (chronic) effects. OSHA admits that compliance does not guarantee welding work will protect the welders from health problems.
It’s true that you don’t see many welders who make it to retirement age as a welder. They either change professions before they reach retirement age, or they end up on disability due to cataracts, back problems or respiratory complications such as COPD, chronic bronchitis, or even lung caner (hexavalent chromium).
Welding Fume Exposure-Acute Effects
The most common acute effect of exposure to intense welding fume is called Metal Fume Fever with symptoms similar to the common flu: chills, low level fever, fatigue, nausea, sore throat, body aches and pains usually lasting 24 hours. Zinc, the coating used in galvanized metal, is often associated with Metal Fume Fever but most other forms of welding fume exposure have also been implicated.
Chronic Illnesses Attributable to Welding Including Cancer, COPD, Tremors, Chronic Bronchitis
There is a variety of components of welded materials and welding methods that may have chronic detrimental effects, including permanent disability, to welders. They include Lead (Pb), Cadmium (Cd), Beryllium (Be), Mercury (Hg), fluorides from fluxes, Iron (Fe), Nickel (Ni), Copper (Cu), Aluminum (Al), and of course Carbon Monoxide (CO) and Carbon Dioxide (CO2).
Chronic effects of exposure to the variety of welding elements can take the form of many serious illnesses. This includes COPD (Chronic welding fume samplingObstructive Pulmonary Disease) COPD is either emphysema or chronic bronchitis. Studies have shown that chronic bronchitis (thus COPD) can be the result of work as a welder over a lengthy period of time. Prolonged exposure to both cadmium and beryllium fumes can cause severe lung complications and pulmonary edema. Long term exposure to mercury fumes is known to cause tremors, emotional problems, and hearing and vision loss. Exposure to lead oxide fumes can permanently damage several main body systems including the reproductive, circulatory and central nervous systems.
It has been confirmed that exposure to hexavalent chromium (also referred to as “Hex Chrome” or “Chrome Six”) from welding on stainless steel or chrome, is a cancer causing substance and specifically regulated by a separate OSHA Standard (29CFR1910.1026). Manganese, a component of many forms of steel and welding rods, has been strongly implicated in causing Parkinson’s-type tremors in welders who have used manganese containing welding rods.
In addition to the toxic effects of excessive exposures to each of these agents, there is the collective effect of exposure to all of the welding emissions which ultimately may result in contracting Chronic Obstructive Pulmonary Disease (COPD). The two most recognized components of COPD are Chronic Bronchitis and Emphysema. Most often, welders diagnosed with COPD have chronic bronchitis. (Of course, smoking history can have a significant effect on development and aggravation of COPD with the most likely effect being emphysema.)
How to Control Welding Fumes?
Logically, the most effective method of control of welding fumes is ventilation. And the most effective form of ventilation to control welding fumes to protect the individual welder is local exhaust ventilation—that is, capturing the welding fumes (the visible smoke) at the point of welding. Though effective in protecting the welder, this manner of ventilation control can be problematic to use because it can introduce oxygen into the area. Applying a strong air current across the point of the weld can cause oxidation, resulting in defective welds.
Further, welding inside a pipe, vessel or container requires a restricted air space that does not allow enough room for adequate ventilation. The inert gas shield around the weld must be preserved while attempting to capture the welding fume before it reaches the breathing zone of the welder or the general air space. Some effective local exhaust ventilation systems have been developed, but the application and control of air capture must be effective but not interfere with the inert gas shield. All this must occur in a work environment that is somewhat less than pristine—as is the case in most welding environments!
An alternative is the use of respiratory protection on the welder. But respiratory protection for welders is the least effective means of controlling exposure, not just because the welder already must wear glasses, a hood, hard hat, leather apron, gloves, and safety shoes but because the variation in welding methods (MIG, TIG, STICK, ARC, TORCH) further exacerbates the ability to uniformly control each worker’s exposure.
This is only a brief summary of the problems encountered during the process of protecting welders from fumes. What’s more, OSHA and industry experts recognize that even if employers are in compliance with all PELs and TLVs for the individual welding components, workers are not necessarily safe from acquiring illnesses at their jobs.
Welding Fume Sampling/Testing
Monitoring welders to determine exposure is relatively easy. Small battery powered air samplers can be clipped to the welder’s belt or apron with a sampling/testing line to a collecting filter clipped to the collar or shield. OSHA states the welding fume sampling/testing devices should be placed outside the welding hood, but some industrial hygienists prefer to sample inside the hood as a truer representation of the exposure. There are exceptions to the outside hood sampling method.
An industrial hygienist will use the Safety Data Sheet (SDS, formerly MSDS) of both the welding consumable and the metal surface that is cut or joined, to identify the components. Lab analysis of metals is achieved by Atomic Absorption (AA) or Inductively Coupled Plasma (ICP).
The best goal for any welding process is to control the individual welder’s exposure to metal fume as much as possible recognizing that OSHA PELs are just a guide, not an ultimate safe limit. Using local exhaust ventilation systems are the most effective but they’re also the most tricky to design so as to not interfere with the welding process. To get the exposure levels as low as you can, it’s important to use controls that have been skillfully engineered to control the fumes for the specific welding method being used. It is also vital to monitor welders regularly to verify the effectiveness of the controls. We recommend monitoring anytime there is a change in welding method (MIG, TIG, STICK) and every 3 years if there is no change in welding method or materials welded.