Choosing ear muffs or ear plugs is a personal choice
Wearing ear muffs or ear plugs for hearing protection is often decided by the personal preference of the worker.
However, one thing that is not optional is the use of hearing protective devices. They must be worn if noise levels exceed 85 dBA (time-weighted average of decibels over a period of eight hours).
Which type of ear protection is chosen by workers will depend upon the fit, comfort and convenience of either ear muffs or ear plugs. Ear muffs, often referred to as headphones, sit on top of your head and cover the ears, sealing out excessive noise. Ear plugs are small devices inserted inside the ear canal.
Neither ear muffs or plugs any good if they aren't worn
One thing is certain: if a worker doesn't like how the ear muffs or ear plugs feel, he/she won't wear them. And the key to avoiding noise hazards is keeping the hearing protection actually on your workers.
And it's the employer's job to ensure that workers are wearing the required PPE for noise control.
Both ear muffs and ear plugs have unique features that offer advantages and disadvantages. The Canadian Centre for Occupational Health and Safety offers a comparison of hearing protection devices.
A hearing protection device's ability to reduce noise is referred to as its "attenuation" - the difference between the hearing threshold when the subject is wearing hearing protection and that when he/she is not, as measured in a laboratory. The higher the hearing protection device's noise reduction rating (NRR), the greater its attenuation.
Ear muffs provide more representative attenuation in laboratory results as compared to in the field because ear muffs are easier to wear.
Ear plugs, on the other hand, are more difficult to insert correctly, and therefore their attenuation (noise reduction) may not be accurately reflected in lab results.
You should look for these features in ear muffs:
- Full-spectrum and low-frequency attenuation
- Extra wide, soft-sealing ear cushions for comfort
- Soft padded headband with low force
- Steel headband, which tolerates temperature extremes
- Push-to-listen button to hear communication
When to wear both ear muffs and ear plugs
If noise exposure exceeds 100 dBA, the National Institute for Occupational Safety and Health (NIOSH) recommends wearing both ear muffs and ear plugs for extra hearing protection in cases of extreme noise such as power saws, pneumatic hammers and jet airplanes at takeoff.
However, doubling up ear muffs and ear plugs does not result in double the hearing protection - since the physical energy of noise doubles with every three decibels.
If, for example, you have two machines each producing 60 decibels of noise, the combined noise level will not be 120 decibels; rather it will be 63. Similarly, if you double up with ear muffs and ear plugs both rated at say, 28 decibels, you will gain only three decibels of protection, for an effective NRR of 31 dBA.
Of course, beyond the wearing of ear protection gear, the use of soundproofing materials can alleviate the noise levels in industrial or commercial settings.