Protecting your Hearing from Permanent Damage

Take the time to learn more about sound levels, duration limits, and steps you can take to protect your hearing.

Occupational safety and health professionals use the Hierarchy of Control to determine how to implement feasible and effective controls. This approach groups actions by their likely effectiveness in reducing or removing the noise hazard.

Elimination or Substitution: In most cases, the preferred approach is to eliminate the source of hazardous noise. When elimination is not possible, substitution of the loud equipment for quieter equipment may be the next best alternative to protect workers from hazardous noise.

Engineering and Administrative Controls: To the extent feasible, engineering controls, administrative controls, and work practices shall be used to ensure that workers are not exposed to noise at or above 85 dBA as an 8-hour Time Weighted Average (TWA). Engineering controls require physical changes to the workplace such as redesigning equipment to eliminate noise sources and constructing barriers that prevent noise from reaching a worker. If engineering controls are not feasible, employers an explore potential administrative controls, such as scheduling that will minimize exposure, providing quiet and convenient lunch and break areas.

Personal Protective Equipment (PPE): When all options for eliminating or reducing the noise at the source are exhausted, hearing protection devices such as earplugs or earmuffs should be made available to workers, at no cost, to sufficiently attenuate noise so that their “real-world” exposure is below 85 dBA as an 8-hour TWA.

Sound level and duration are important to consider when protecting your hearing from damage.

Sound Pressure Level

Pressure wave traveling in air or water
Expressed in decibels (dB) – It is the perceived loudness
Analogy: surface wave made when you throw a stone into a calm pool of water
Logarithmic scale
Small dB increase represents large increase in sound energy.
3 dB increase is a doubling of sound energy
10 dB increase represents a 10-fold increase
20 dB increase represents a 100-fold increase

Time to Reach 100% of Daily Dose	Exposure Level per NIOSH REL	Exposure Level Lawrence University Beyond Limits	Protection Required – Noise Reduction Ratio (NRR)
8 hours	85 dBA	75 dBA – reduced from 85	NNR 25
4 hours	88 dBA	80 dBA – reduced from 88	NNR 25
2 hours	91 dBA	85 dBA – reduced from 91	NRR 25 w/ear muffs
1 hour	94 dBA	85 dBA – reduced from 94	NRR 25 w/ear muffs
30 minutes	97 dBA	85 dBA – reduced from 97	NRR 25 w/ear muffs
15 minutes	100 dBA	85 dBA – reduced from 100	NRR 35 w/ear muffs

Noise exposure levels and required personal protection.

Examples of tools and their sound levels by decibels.

Signs of Hearing Loss Include:

Frequently asking people to repeat themselves.
Turning an ear in the direction of sound in order to hear it better.
Understanding conversation better when you look directly at the person. Seeing their facial expression and lips movements can help a someone understand another better is there is a hearing problem.
Being unable to hear all parts of a group conversation.
Experiencing pain or ringing in the ears (tinnitus).
Listening to the TV or radio at volume levels higher than other people normally listen to.

If any of these signs are displayed, a person can take action by visiting an audiologist for a hearing test. An audiologist is a health professional who specializes in diagnosing and treating people with hearing problems.