The noise path

11 Nov 2019

WorkSafe NZ has produced a series of resources designed to mitigate the risk of hearing loss in noisy workplace environments. While the importance of hearing protection is widely understood, there are other steps that should be prioritised to minimise the threat of hearing loss due to excessive noise exposure.

There are three places where noise occurs:

  • At the source of the noise, i.e. the equipment/vehicle
  • Along the path i.e. where the noise travels from the source to the worker
  • At the worker

Managing risk at the source

The first step is to identify the source of noise and its associated risk so you can ascertain how to manage it. The most effective way to reduce noise at a workplace is to remove the source:

  • Ascertain whether it is a design issue or if processes need to be changed.
  • Check that the equipment is not damaged and has been correctly maintained as both these things can contribute to harmful noise levels.
  •  Implement a ‘buy quiet’ policy for when purchasing new equipment or vehicles, which establishes a maximum acceptable noise level.
  • If equipment becomes noisy and this cannot be reduced through repair or maintenance, replace the equipment with a new, quieter option.

Managing risk along the path

  • Where possible, install noise absorption materials in the workplace to reduce reflected noise.
  • Move the source away from workers, for example move it to a control room where the equipment can be operated remotely or place the equipment outside the building in a ventilated enclosure covered in sound absorbing material.
  • If the noise can’t be isolated, create a noise barrier or screen between the source and workers using acoustic panels.

At the worker

  • Rotate workers to reduce the time they spend around noisy equipment or vehicles.
  • Train and supervise workers on how to protect themselves and what personal protective equipment they should be wearing.
  • Ensure hearing protection equipment is available at all times (please note, this is the least effective control measure)

Office spaces

Even if your workplace does not use or handle noisy equipment, workers can still be exposed to hazardous noise levels. These include:

  • Plumbing
  • Air conditioning
  • Lifts
  • Common corridors
  • Noisy business activities (such as a bar at the top of a building)
  • Vibration


While you may not have the luxury of designing a new workspace with focus on minimising noise, there are measures that can be taken for existing space to reduce noise such as insulation, floors and wall coverings and designated quiet zones.

For more information, we recommend you visit the WorkSafe NZ website.