The Occupational Safety and Health Administration (OSHA) has published a new safety and health information bulletin outlining the role of hearing protector fit testing (HPFT) in workplace hearing conservation programs. While hearing protector fit testing is not required under OSHA’s Occupational Noise Exposure standards, the agency describes it as a valuable training and verification tool.
The bulletin applies broadly to employers covered under OSHA’s occupational noise regulations. Under federal standards, employers must implement a hearing conservation program when employees are exposed to an eight-hour time-weighted average of 85 A-weighted decibels (dBA) or greater.
Repeated exposure to noise at or above this threshold can contribute to hearing loss and other adverse health effects. OSHA emphasizes that elimination, substitution, and engineering controls should be prioritized before relying on personal protective equipment such as hearing protection devices (HPDs).
Hearing protector fit testing and hearing conservation programs
Hearing protector fit testing measures the amount of noise reduction, or attenuation, a hearing protection device provides to an individual worker. The result is reported as a personal attenuation rating (PAR), which reflects the actual protection achieved when the device is properly inserted.
OSHA notes that each worker’s ear canal size and shape are unique, meaning attenuation levels may vary even when employees use the same earplug model. Hearing protector fit testing verifies whether an individual has achieved adequate protection and can reinforce proper insertion techniques during training.
Traditional hearing protector selection often relies on the noise reduction rating (NRR), a laboratory-derived value intended to estimate potential attenuation. However, real-world attenuation frequently differs from labeled NRR values. OSHA clarifies that hearing protector fit testing does not replace the required selection methods listed in Appendix B of the Occupational Noise Exposure standard. Instead, fit testing can confirm whether a worker has achieved sufficient attenuation with the selected device.
Objective and subjective hearing protector fit testing systems
The OSHA bulletin describes two types of hearing protector fit testing systems:
- Subjective systems, which require workers to respond to sounds played through headphones. These systems establish a baseline without hearing protection, followed by testing with the HPD inserted.
- Objective systems, which use microphones to measure sound levels inside and outside a modified earplug. These systems do not rely on worker responses and typically provide results more quickly, though they may be limited to specific HPD brands or styles.
When selecting a hearing protector fit-testing system, OSHA recommends evaluating whether the device meets the ASA/ANSI 12.71-2018 performance criteria. Employers should also consider cost, calibration requirements, compatibility with available HPDs, background noise monitoring capabilities, testing time, and how PAR results are reported.
Some systems report PAR as pass/fail, while others provide numerical values. OSHA notes that numerical PAR reporting may be more useful in workplaces where noise exposure levels vary.
Implementation and documentation considerations
Although hearing protector fit testing is not mandated under OSHA’s noise standards, the agency acknowledges its value as a training tool. OSHA has incorporated fit testing into its own hearing conservation program.
The bulletin recommends that employers consider:
- Conducting initial fit testing prior to or shortly after enrollment in a hearing conservation program
- Providing annual fit testing to reinforce training and verify attenuation
- Repeating fit testing when new HPDs are introduced
- Using fit testing to support follow-up procedures when a standard threshold shift occurs
Records generated through hearing protector fit testing may help document employer efforts to ensure proper fit and effective attenuation, particularly during inspections or internal audits.
Relevance for laboratory environments
The guidance applies broadly to employers covered under OSHA’s occupational noise standards and does not single out any specific industry sector. However, laboratory environments that include high-noise equipment or mechanical systems may be subject to OSHA’s occupational noise requirements if exposure thresholds are met.
For laboratory managers and environment, health, and safety personnel, the bulletin highlights the importance of evaluating whether hearing conservation programs verify individual attenuation performance, not just device selection.
This article was created with the assistance of Generative AI and has undergone editorial review before publishing.
