Document ID: chunk:federal_register_of_legislation:F2016L00426:reg:10:p5
Version: federal_register_of_legislation:F2016L00426
Segment Type: reg
Provision Reference: reg 10 (pt 5/5)
Character Range: 97273–99604

noise will escape through any gaps. Failure to line the inside of the guards could result in an increase in noise at the operator's position if the gaps have been minimised as in (i) above.
In most cases, both sets of modifications can be tested in mock-up form using cardboard (and wide tape) to extend the guarding and temporarily fitting areas of acoustic foam inside. Not only does this process help with the practical aspects (access, visibility etc), but it usually also provides a very good indication of the noise reduction that can be expected. Guard vibration radiated as noise can also be treated via damping (as above).

  9.      CHAIN & TIMING BELT DRIVES

Technique
Noisy chain drives can often be replaced directly with quieter timing belts. Within the range of timing belts available, there are also quiet designs that use different tooth profiles to minimise noise. There is also a new design of belt for applications where noise is critical which uses a chevron tooth pattern to provide very quiet running. Noise reductions in the range of 6 - 20 dB are often possible using this approach.

  10.  ELECTRIC MOTORS

Technique
Most companies have large numbers of electric motors used on anything from fans to pumps to machine tools. However, it is not very common knowledge that general duty motors are available (at little or no cost premium) that are up to 10 dB(A) or more quieter than typical units as direct replacements. The best approach is to feed these motors into the system over a period of time so that all replacement motors are quiet motors.

[1] The adjustment factor for extended workshifts shown in Table 3 of this Code is taken into account.
[2] Guidance for designers of buildings on recommended background sound levels (i.e. noise coming from outside the room or from building services) for different types of workplaces can be found in AS/NZS 2107:2000 Acoustics – Recommended design sound levels and reverberation times for building interiors.

[3] Morata T.C. (2007) Promoting hearing health and the combined risk of noise-induced hearing loss and ototoxicity, Audiological Medicine, Vol.5, Issue 1, pp33-40.
[4] Based on Health and Safety Executive UK guidance material with the points used in the tables derived from procedures in AS/NZS1269.1
[5] Source Health and Safety Executive UK