Metal fabrication industry
Noise in the metal fabrication industry
Typical noise sources
Noise control measures
Noise in the metal fabrication industry
In the metal fabrication industry, people are generally subjected to noise of a varying nature. High noise levels, particularly those of short duration such as impulse or impact noise, are present in many metal fabrication workshops and are capable of causing damage to hearing. The metal fabrication industry in Australia is responsible for a large proportion of workers' compensation payouts for noise induced hearing loss of workers.
In metal fabrication workshops, noise levels can be expected to range between about 80 - 125dB(A). Most common noise sources are from angle grinders, metal presses, cutting saws and hammering and bashing on metal objects.
Further sources may be found from welding and gouging, which all cause high noise levels to be emitted. Because these types of noise emissions are generally of short duration, (e.g. a few belts with a sledge hammer on a metal plate or using an angle grinder to clean up a weld), the use of personal hearing protectors is often ignored or simply not even considered.
However, these relatively short duration exposures happen many times per shift and may therefore pose a serious hazard to hearing. Further, impact noise, such as from bashing on metal plates or dropping metal objects on workbenches or floors are, because of their impulsive nature and the way our ears operate, potentially more hazardous to hearing than noise such as that from machines.
Typical noise sources
Some typical noise sources at operator ear level in the metal fabrication include:
| Hammering on metal objects | 115 - 120 dB(A) |
| Punch press | 102 - 107 dB(A) |
| 9 inch angle grinder | 97 - 106 dB(A) |
| Gouging | 97 - 99 dB(A) |
Noise control measures
As with all risk exposures in the workplace, risk management must be applied through a hierarchy of control measures, such as elimination, substitution, engineering and/or administrative controls, and as a last resort (or as an interim measure), reliance on protective equipment.
Noise exposure in the metal fabrication industry should primarily be controlled through engineering and/or administrative noise control measures.
Examples of engineering noise control measures include:
- locating noisy equipment such as air compressors and power presses in separate enclosures
- providing a sound proof enclosure for operators
- using mobile enclosures where noisy work has to be carried out.
Examples of administrative noise control measures are:
- scheduling noisy work from various fabrication activities into a particular part of the shift, (e.g. early morning or late afternoon, with quieter work activities for the remainder of the work period)
- signposting entries to areas in which the use of a hearing protector is mandatory for everyone in the areas.
Where noise control cannot be achieved through these measures the relevant obligation holder (e.g. the employer), must provide suitable personal hearing protectors as well as proper instruction in their use, so that exposed workers can perform their work in a manner that is safe and without risks to their health and safety.
