NIOSH recommends noise exposure limit as time-weighted average of 85 decibels over 8-hour period
Workers in certain subsectors of the health care and social assistance (HSA) industry experience hearing loss at a rate higher than expected "for an industry that has had assumed 'low-exposure' to noise," according to a recent study from NIOSH.
For nine years (between 2003 to 2012), researchers analyzed hearing tests for 1.4 million American workers, of whom 8,702 worked in the HSA sector. Findings showed that all subsectors of HSA except hospitals posted higher risks of hearing loss than the reference industry used in the study. Child day care services, ambulatory and health care services, offices of other health practitioners, community food and housing and emergency and other relief services were among highest-risk sectors.
The researchers cited a previous study that determined sources of noise in HSA environments include orthopedic instruments like cast cutters and dental instruments.
Another study said that noise levels in a hospital emergency room reached peak levels in excess of 85 dBA occurring at least once per minute from monitor alarms, overhead speakers and slamming doors. High noise levels also were reported in operating rooms, hospital kitchens, intensive care units, hospital laundry facilities and around helicopter emergency medical crews.
The institute's recommended exposure limit for noise is a time-weighted average of 85 decibels over an 8-hour period.
"OSHA also recommends using acoustical treatment on laboratory walls and ceilings, moving as much noise-producing equipment as possible out of the lab and into equipment rooms, and situating remotely the compressors for temperature-controlled rooms," the researchers wrote.
NIOSH researchers pointed to successful noise reduction practices used in some hospitals, including lowering volumes on alerting bells and phones, using floor mats and modifying equipment.
But loud noise is not the only potential contributor to hearing loss. Some drugs – including anticancer, anti-inflammatory, antithrombotic, antimalarial and antirheumatic drugs – are classified as ototoxic, meaning exposure to them can elevate workers' risk for hearing damage.
"Exposure to chemotherapy drugs can be better prevented by using closed-system transfer devices for administering drugs, using double gloves and single-use gowns, improving awareness of risks among staff, and fostering a 'blame-free' environment for reporting spills," the researchers wrote, citing other studies.