Health and Safety

Noise

How much noise is too much?

As a rough guide; there are some tests which individuals can do when equipment is being used and the sound or noise is being emitted, these are:

  • Is the noise or sound level intrusive for most of the working day? (e.g. like a busy street, a vacuum cleaner or crowded restaurant)
  • If 2 individuals standing 2 metres apart need to raise their voices to have a normal conversation.
  • Do you use noisy powered tools or machinery for over half an hour a day?
  • Do you work with noisy equipment routinely?
  • Is noise generated because of mechanical impactions (e.g. hammering, pneumatic impact tools or explosive sources e.g. cartridge operated tools or destructive pressure testing)
  • Do you have muffled hearing at the end of the day, even if it is better by the next morning?

 If you answer “yes” to any of test questions this is a good indicator that the sound is a hazard in the working space.

To identify how individuals can be best protected, it is necessary to conduct a noise monitoring survey. This can be organised through contacting the Health & Safety Team. If a noise monitoring survey has already been done in a room, and the equipment or function of the room significantly changes, the survey will need to be repeated.

What can be done to reduce the sound levels in my area?

Sound and noise are often produced by moving equipment. Often the levels alter when the equipment experiences wear and increased vibration of the mechanical parts. A hierarchy of control exists to minimise noise levels within work spaces. The most effective control is to stop sound or noise being generated at source. The hierarchy is:

  1. Purchase low noise level equipment (quiet operation models)
  2. Conduct regular maintenance, replacing worn parts to minimise mechanical vibration
  3. Build in noise minimisation equipment into the equipment set-ups e.g.
    1. Sound absorbing casing
    2. Vibration absorbing matting
    3. Sound baffles in duct work
    4. Soft furnishings (where appropriate) to absorb rather than reflect sound waves in a room
    5. Reduce the quantity of time the equipment is operating for (emitting sound), or restricting the exposure time of individuals (for example job rotations)
    6. Increase the distance between the item generating sound and the individual e.g.
      1. If the equipment does not require direct supervision, people leave the work area
      2. People work away from the source of noise
      3. Using PPE. Different PPE options protect from different sound levels and sound frequencies. To ensure that the correct PPE has been selected, it is necessary to have completed a noise monitoring survey. It is also essential to fit PPE properly to ensure there is an adequate barrier to the sound waves and the PPE will provide appropriate protection.

 Early symptoms of hearing loss

There are a few early signs of hearing loss. Hearing loss is generally gradual and in many cases by the time individuals have noticed the symptoms, their hearing has already been affected. The best protection is to prevent damage from occurring. If you are exposed to sound or noise and notice the symptoms listed below then you should contact the University Occupational Health service.

  • Conversation becomes difficult or impossible
  • Your family complains about the television being too loud
  • You have trouble hearing the telephone
  • You find it difficult to differentiate sounds like “t”, “d” and “s”, so you confuse similar words
  • Permanent tinnitus (ringing, whistling, buzzing or humming in the ears) can also be caused.

 Policies and guidance documents