Photobiological hazards in shielded metal arc welding

Area of Science:

• Occupational Health and Safety
• Photobiology
• Welding Technology

Background:

• Artificial optical radiation from welding presents photobiological hazards.
• Shielded Metal Arc Welding (SMAW) is a common technique used in occupational and domestic settings.
• Previous research investigated robotic arc welding, necessitating further study on manual processes.

Purpose of the Study:

• To assess photobiological hazards from optical radiation during Shielded Metal Arc Welding (SMAW).
• To evaluate exposure limits for blue, visible, ultraviolet, and infrared light emitted during SMAW.
• To expand on previous investigations of robotic arc welding by focusing on manual techniques.

Main Methods:

• Measurements of irradiance were taken using three dedicated sensors during typical SMAW procedures in a laboratory setting.
• European Directive 2006/25/EC and occupational exposure limits were applied.
• Field measurements and analysis of various welding parameters (currents, electrodes) were conducted.

Main Results:

• Overexposures to optical radiation were detected in all spectral bands, including sub-minute and one-second durations at close distances.
• Initial welding procedures, especially without Personal Protective Equipment (PPE), showed exposures near the established limits.
• Simulated 'bad' welding practices resulted in significantly increased radiation exposure.

Conclusions:

• SMAW poses significant photobiological risks, necessitating adherence to safety protocols.
• Training is vital to ensure correct welding procedures and minimize exposure.
• The risk to nearby workers must also be considered, highlighting the need for comprehensive risk assessment and potential mitigation strategies for occupational diseases.