Welding and Noise

Thanks to public and private safety organizations' efforts, many workers understand that frequent exposure to loud noise has negative health impacts; chief among these is irreversible hearing damage. Other lesser-known effects include annoyance, elevated blood pressure, stress, speech interference, and tinnitus. Welders are often exposed to hazardous noise levels due to their equipment and operations, and are at risk of occupational hearing loss.

According to the Occupational Safety and Health Administration (OSHA), noise levels over 85 decibels, averaged over an eight-hour workday, are potentially hazardous to your hearing. The OSHA standard uses a five dBA exchange rate, which means that when the noise level is increased by five dBA, the amount of time a person can be exposed to that noise level is cut in half. For example, OSHA's eight-hour permissible exposure limit (PEL) for noise is 90 dBA. If an employee were exposed to noise at an average level of 95 dBA, it would limit the allowable exposure duration to four hours (considering no hearing protection is worn).¹

The Health and Safety Executive (HSE), a United Kingdom governmental agency, details the noise levels associated with different tasks within the welding process² in the table below. Except for TIG welding, electric arc welding generates harmful levels of noise.

Actual noise levels depend on several factors. The following factors can increase noise:

• Increasing consumable diameter
• Increasing current
• Thicker material
• Stainless steel versus mild steel

To protect workers, employers must follow the hierarchy of controls, as shown below.

Eliminating the process is not always feasible; therefore, the next best options are substitution, engineering controls, and administrative controls such as training and work scheduling. Finally, personal protective equipment (PPE) is the least effective control and should always be used as a last resort.
HSE recommends the following controls, where feasible²:

• Consider "reduced noise" air nozzles when plasma cutting and air arc gouging as the dominant source of noise is the high-pressure compressed air
• Move from hand-held plasma cutting to an automated submerged plasma cutter, which can reduce noise levels to below 80 dBA
• Use a wire/rod size and current appropriate for the job and not excessively large
• Ensure that gas velocity for plasma cutting and arc gouging is as low as possible
• Weld in open spaces as opposed to areas where sound may be reflected, such as the corner of a workshop, or add sound-absorbing materials to reflective surfaces

References

1. https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.95
2. https://www.hse.gov.uk/welding/health-risks-welding.htm