Welding smoke is a mixture of various gases and metal fumes. Its composition varies depending on the welding method and the material being treated.
The following substances are typically found in welding smoke:
- Iron oxides – oxides from additives and various steel grades, e.g. manganese, chrome, nickel, calcium, copper, potassium, barium
- Fluorides – oxides from painted structures or structures with other surface treatments, e.g. zinc, lead, chrome
- Shielding gas as an impurity: argon, carbon dioxide, helium
- Gases generated near the electric arc: carbon monoxide, nitrogen oxides, ozone
Welders have a 20–40% higher risk of lung cancer than office workers, for example. Among welders, the risk of asthma is double in comparison with office workers. When assessing the permanent health risks related to welding, the employee’s specific risk of illness must be considered, including atopy and particularly smoking, which further increases a welder’s risk of lung cancer, as well as making their pulmonary functions significantly weaker when combined with the qualities of welding smoke that irritate the respiratory tract.
The International Agency for Research on Cancer (IARC) recently examined scientific evidence and came to the conclusion that exposure to steel welding fumes, even mild ones, may cause lung cancer and even kidney cancer. Other respiratory tract diseases caused by welding fumes include metal fume fever, which may be caused by welding galvanized steel, for example.
The employer’s responsibility for a healthy work environment
According to labour legislation, the employer is responsible for providing a safe and healthy workplace. To ensure this, the employer needs to be aware of the harmful effects and risks in the workplace and their management. The employer has an obligation to monitor the work environment, identify and assess work-related risks and implement the necessary corrective measures, as well as monitoring the effects of such measures on safety and health at the workplace.
The solution: local exhaust ventilation or air purifier
Local exhaust ventilation is used to remove dust, smoke, chemicals, odor, welding gas or other air impurities from a work area. Unless impurities are managed where they arise, they will spread around the work facilities.
In local exhaust ventilation, the challenge is the energy wasted through the exhaust fans: they blow warm air from the facility into the outside air. This causes major energy losses in the winter in particular, meaning that there is a need to improve heat recovery.
When selecting an air purifier, the quality of the impurities in the facility should be identified first, as purifiers are optimized for different types of particles, gaseous substances or oil mist. Many purifiers also take into account the layering of impurities in the indoor air in the facilities: purifiers take in air at a height of 2.5 metres and higher and blow out purified air from the bottom part of the device at the exact level where employees are working. This reduces the need for cool replacement air, as the impure air is not blown out of the facilities. This also reduces energy costs.