Hearing Protection Devices (HPD's)
There are several styles of hearing protection devices available. The best choice is the one that fits properly, is appropriate for noise and work environment, and is comfortable and consistently worn by the individual. It is a requirement that employees receive individual fitting instruction including assessment of their fit.
What type of hearing protection devices must an employer provide?
Employers are required to provide a minimum of two types of hearing protectors to noise exposed workers. It might be advantageous to offer additional styles. What is appropriate for one worker or setting is not always appropriate for another. The HPD comparison chart summarizes the features and applications of each hearing protector type.
| Device | Features | Disadvantages | Applications |
|---|---|---|---|
Foam Plugs  |
|
|
|
Pre-Formed Plugs  |
|
|
|
Banded/Semi-Insert  |
|
|
|
|
|
|
|
|
|
|
How do I know if the hearing protector is fitting properly?
Each employee within the hearing conservation program needs an individual assessment of hearing protector fit. Properly fitted earplugs create an airtight seal in the ear canal. Once inserted, a gentle tug on the plug will be met with resistance and there should be an evident break in the seal upon removal. Earmuffs should be in good condition since proper fit requires adequate headband tension and cushion integrity. The cushion seal around the ear should be traced carefully to ensure there are no gaps.
Why is HPD selection so important?
A hearing protector serves no purpose unless it is worn.
- Employees generally will not wear devices that are uncomfortable.
To comply with safety policy, individuals may modify HPD’s for greater
comfort or wear them “just for show”, either of which
will greatly compromise or nullify effectiveness.
- Hearing protectors should be convenient and quick to put on
or they are unlikely to be worn, particularly for short,
intermittent exposures. Individual reports of being unable to
hear well when wearing HPD’s should not be disregarded.
- An employee’s overall safety and job performance frequently requires the ability to hear critical communication and warning signals. While some new wearers will require a brief adjustment to communicating with the devices, there are situations in which a different protector will be needed. Employees with hearing loss may need special, filtered plugs or electronic earmuffs. Individuals working in environments of 80 to 85 dBA may be overprotected by high NRR devices, compromising their ability to hear potentially critical alerts and warnings.
What should I know about the Noise Reduction Rating (NRR)?
The Noise Reduction Rating (NRR) system was developed to provide consumers with an estimate of how many decibels of noise reduction can be achieved by any given hearing protector. The ratings are established as a result of measurements performed under controlled laboratory conditions. The “real-life” protection provided by hearing protectors is often significantly less than the ideal or measured value. It is recommended that the NRR be de-rated by one-half to estimate actual noise reduction in workplace conditions. Example: Joe’s noise exposure is 94 dBA and he wears earplugs with a manufacturer NRR of 26. His estimated noise exposure when using the plugs is 81 dBA (94–13=81).
If desired, the actual noise reduction of a hearing protector as worn by the employee can be obtained using the FitCheck system.
How much noise reduction should the hearing protector provide?
Ideally, hearing protectors should provide enough noise reduction to bring employees’ noise exposures to safe levels without significantly compromising their ability to hear important communication and warning signals. The chart below provides a guideline.
Adjusted Employee Noise Exposure Level (as a result of HPD Use) Outcome
How is hearing protection level affected when HPD’s are removed for short periods of the noise exposure?
In order to get maximum benefit from a hearing protector, it should be worn at all times during noise exposure. Even a brief removal of the HPD will result in a substantial reduction in protection.
