Hearing protection is a serious matter - once it's gone, it's gone! The good news is, keeping everyone safe from excessive noise in the workshop doesn't need to be complicated - keep reading for your so quick, so easy guide to workplace hearing protection...
The important facts...
- Exposure to excessive noise (over 85dB) can cause permanent hearing loss
- Damage to hearing is one of the most wide spread, yet preventable workplace injuries
- Hearing loss generally occurs over time, so may not be immediately noticeable
When does hearing protection need to be worn?
Any area where noise levels exceed 85dB you need to wear hearing protection. 85 decibels (dB) is about the level of noise from city traffic from inside your car. Any level above this can cause damage, the level of damage depending on the level of noise and length of exposure.
Worksafe suggest "If you have to raise your voice to have a normal conversation when standing about a metre apart, for at least part of the day, then noise levels on the site could damage hearing." Hearing protection alone should not be relied on to control noise exposure in noisy environments - click here for Worksafe's guide to managing risk relating to noise in manufacturing.
What is the best type of hearing protection?
Earplugs, earmuffs or both?
In terms of the level of hearing protection (or noise reduction) provided, both earplugs and earmuffs are capable of providing the same level (provided they are used correctly of course). Australian/New Zealand Standard, AS/NZS 1270: 2002 tests hearing protective equipment and gives it a classification rating between Class 1 and 5 - Class 5 being the highest.
Of course determining the best type of protection is not solely about whether or not it is capable of doing the job. You also need to factor in a few things like:
- What other PPE is being worn? - Choose something that will not be affected by other PPE - eg. slimline earmuffs that fit under helmets, hardhat earmuffs, or earplugs that don't get in the way of anything!
- How long is the equipment being worn for, and how often? - Choose something that will be comfortable for the wearer. Uncomfortable equipment can make workers reluctant to wear it, or make them want to constantly adjust it or take it on and off which is dangerous.
New Zealand Hearing Protection Standards
A Class 5 rating is the highest standard for hearing protection under AS/NZS 1270:2002. Classes represent the decibel reduction that can be expected from that particular ear protection product.
To choose the correct class level for your needs, you'll first need to know the level of noise you are potentially being exposed to. In general, most manufacturing workshops can expect noise levels to exceed 100dB due to the equipment being used - click here for a general guide to noise levels.
Once you know the noise level (in decibels) you're likely exposed to, subtract 80 from this level and you'll have a reduction indicator number. This number can be used against the Class rating to select the minimum protection rating for your requirements. For example, if your level of exposure is 105dB: 105 - 80 = 25, so your reduction indicator number is 25, meaning you would need earplugs or earmuffs with a Class 4 or 5 rating.
|Class Rating||Workplace Noise Levels||SLC80 dB Reduction Range|
|1||Less than 90dB||10 to 13|
|2||90dB to less than 95dB||14 to 17|
|3||95dB to less than 100dB||18 to 21|
|4||100dB to less than 105dB||22 to 25|
|5||105dB to less than 110dB||26 or greater|
Hearing Protection Selection Guide