Laser Fumes Present Health Hazards
Laser and plasma cutting heat materials to very high temperatures, producing smoke which can have immediate and long-term consequences for health.
Dangerous Laser Fumes
Laser cutting creates many different chemicals and compounds. Heating metals to the temperatures involved in the cutting process forms dozens of oxidized compounds that can be harmful when inhaled.
The specific health risks are well-documented. Chromium is used to plate metals, and it is added to alloys for corrosion resistance. Chromium is what makes stainless steel stainless. The cutting of stainless steel creates hexavalent chromium, the dangerous form of chromium.
Immediate exposure to hexavalent chromium can cause skin sores. It can also irritate the eyes, nose and throat. Nosebleeds and red, itchy rashes can occur with repeated exposure. Furthermore, it is known to cause cancer in those exposed to it. In 2006 OSHA published a new rule for hex chrome exposure, which drastically reduced the permissible level of exposure in the workplace, from 52 to 5 micrograms per cubic meter (µg/m3) – a tenfold reduction. If the material being cut is a chromium-containing alloy, HEPA filters may be necessary to achieve compliance.
Nickel, another common element in alloys, is also a known carcinogen. It can also cause heart and kidney problems.
Manganese is another serious hazard. Its worst effect is brain and nervous system damage. Manganese exposure, which is most common in welders but also occurs with laser and plasma cutting, causes neurological damage. Symptoms resemble Parkinson’s disease with tremors, difficulty moving the arms and legs, and muscle stiffness. The damage is permanent.
Many other materials found in laser smoke are dangerous. Beryllium, often used in aircraft parts and other lightweight materials, causes the fatal lung disease berylliosis.
Lead is a well-known poison. Cadmium and cobalt, found in small amounts in many industries, are also known to cause cancer. OSHA has urged companies to phase out the use of these two elements whenever possible.
Laser Fume effects
Smoke from laser and plasma cutting is a complicated mixture. There are many different side effects of exposure to it. The most common effect is irritation of the eyes, nose and throat.
Metal fume fever, linked to zinc fumes, is another common problem for anyone exposed to these vapors. Symptoms resemble a flu virus: headaches, chills, muscle aches and coughing.
Those regularly exposed to metal smoke are more likely to get infections such as pneumonia and bronchitis. Damaged lungs are easier for germs to infect. Long-term exposure can cause fibrotic lung disease. This occurs when the lungs are damaged repeatedly over a long period of time.
The exposure can also cause chronic obstructive pulmonary disease (COPD). Controlling exposure can help prevent these conditions.
Not only lungs
According to research, smoke from plasma and laser cutting don’t just damage the lungs.
Laser and plasma cutting produce metal particles small enough to be absorbed into the body through the lungs. People exposed to excessive amounts can have measurable amounts of these in their blood. Many stay in the body for a long time. This means that a person who breathes these every day will have high levels built up in their blood.
The kidneys are the organs that remove waste materials from the body. Metals, especially hexavalent chromium and cadmium, are toxic to the kidneys.
Metal fumes have also been found to cause cardiovascular disease. People regularly exposed to these in jobs like welding and plasma and laser cutting have a higher risk of strokes, heart attacks and coronary artery
To manage the risk associated with hazardous laser fumes, plasma and laser cutting tables need to be equipped with a fume extraction system. General ventilation, however, is not typically enough to prevent dangerous levels. In areas where cutting is being done without proper fume control, it’s often possible to see a visible haze of particles in the air.
To ensure proper removal, quality filters must be changed regularly. Air being returned to or vented inside the facility must be filtered as well. It is recommended that filters used in these collectors be rated MERV 15. This means that they are efficient at capturing particles as small as 0.5 microns, which is efficient enough to capture the small particles produced in plasma and laser cutting.
If the material being cut is stainless steel, additional HEPA filters may be needed. Stainless steel produces high levels of hexavalent chromium when cut, and it must be filtered with great efficiency. Other alloys, such as various types of steel, may also require HEPA filtration if they release dangerous compounds like hexavalent chromium or beryllium.
Laser fumes cannot be vented directly outside without being filtered, because they contain toxic materials.