Hearing Conservation

In Washington State, noise levels greater than 85 dBA for an eight hour time-weighted average is considered hazardous. If the workplace noise levels indicate employees are exposed to hazardous noise, you must conduct noise monitoring to gain an accurate measurement of employee’s exposure.

Situations that indicate exposures that equal or exceed 85 dBA TWA8

• Feeling the need to speak louder while standing an arm’s length from the receiver.

• Noise information from the manufacturer.

• Reports from employees.

• Warning alarms are difficult to hear.

• Work near abrasive blasting or jack hammering.

• Use of tools such as the following:

  o   Heavy equipment

  o   Fuel-powered hand tools

  o   Impact tools

  o   Compressed air driven tools

  o   Power saws, grinders, chippers

  o   Powder-actuated tools

  o   Lawn care tools: weed eaters, leaf blowers, lawn mowers, chain saws

FB Safety members can request a noise monitoring visit by contacting us. You can also request a Labor and Industries consultation free of charge.

Common Sources of Hazardous Noise in Agriculture

Survey the area where the noise is being produced. Common noise sources are motors, compressed air, moving parts on equipment (conveyors, gears, rollers, etc.)., dryers, shakers, product dropping onto equipment, forklift alarms.

Noise travels in waves and can be amplified when combined with multiple sources. It can also reverberate, traveling from a source to the concrete floor or stainless-steel equipment and back at the receiver.

• Modify or eliminate equipment:

  • Can the process operate without it?

  • Replace it with quieter equipment.

  • Reduce air pressure.

  • Add a muffler or silencer.

• Perform regular maintenance:

  • Lubricate belts

  • Tighten loose or unbalanced parts

  • Replace worn bearings

• Isolate noise sources in separate rooms or enclose them with barriers between them and the receivers.

• Install sound-absorbing materials to catch the sound waves rather than reverberating them, which adds to amplification.

• Adjust work schedules to minimize employees’ time spent in noisy areas.

• Rotate employees between noisy and quieter areas.

• Take breaks so the delicate parts of employees’ ears have time to recover.

• Educate employees about their risk of noise exposure, the permanent effects of hazardous noise whether it is at work or at home, and how they can minimize their risk of hearing loss.

Remember this is the last option in the hierarchy of controls. There is a lot of human factors that goes into wearing hearing protection properly. If you cannot reduce employee exposure to below the hazardous threshold:

• Find hearing protectors that your employees approve of. If they don’t find it comfortable, they won’t want to wear them.

• Provide two types of hearing protectors for employees to choose from. This is a requirement.

• Ensure the hearing protectors are adequate. Use the noise reduction rating (NRR) usually posted on the packaging to determine if the hearing protectors will provide adequte reduction from the noise level you measured.

• Subtract seven dB from the posted NRR. The NRR determined by the manufacturer is in ideal settings. For example, your ear plugs reduce noise by 32 dB. The actual noise reduction will be 25 dB (32 dB – 7 dB).

• Train employees to wear them properly and the importance of wearing them properly.

• Prior to first assignment involving noise exposure to greater than 85 dBA TWA8.

• At least annually thereafter.

• Include:

  • The effects of noise on hearing;

  • Noise controls at the workplace;

  • Purpose, types, and importance of proper hearing protectors;

  • Instructions about selecting, fitting, using, and caring for hearing protection;

  • The purpose and procedures for evaluating your program;

  • Employees’ right to access noise related records.

• Maintain a written description of the initial and refreshing training.

L&I Hearing Protection Training Kit

L&I Hearing Protection Online Employee Training

L&I Noise Audit Training

NIOSH They’re Your Ears Handout

Audiometric testing establishes a reference point for an individual’s hearing and detects changes in hearing ability over time. They can provide early detection of hearing loss that may go unnoticed, allowing for prompt intervention and adjustment to hearing conservation programs.

Audiograms must be:

• Conducted at not cost to the employees;

• Completed within 180 days of employees first assignment to areas with hazardous noise, and at least annually thereafter;

• Compared to the baseline (initial) audiogram to identify standard threshold shifts;

• Are reviewed by an audiologist, otolaryngologist, or other qualified physician;

• Kept for records.

If employees are expected to be assigned to duties with exposure to hazardous noise for less than one year, can conduct hearing protection audits or use third-party hearing loss prevention programs. If you choose to conduct audits, you must:

• Conduct audits at least quarterly;

• Ensure the audit is representative of all processes and work activities in your workplace;

• Cover all employees present on the day of the audit;

• Assess exposures and hearing protection for the full shift for each employee covered at the time of the audit;

• Ensure staff conducting the audit are properly trained;

• Assess the hearing protection used by each employee during the audit;

• Document audits.

Document your hearing conservation program, including:

• Exposure measurements for at least two years and for as long as you rely on them;

• Audiometric test records for the duration of employment of affected employees;

• Hearing protection audits, if you choose to rely on them, for the duration of employment of affected employees.

Hearing Conservation Program Template