Hearing Conservation
HPD Noise Reduction
- HPDs must reduce employee noise exposure below an 8-hour TWA of 90 decibels
- Employees with STS, noise exposure reduced below an 8-hour TWA of 85 decibels
- Noise reduction ratio (NRR)
- Lab versus real world
- Ear plugs: use 1/3 of NRR
- Earmuffs: use 1/2 of NRR
