Pilot task-based assessment of noise levels among firefighters

Abstract

PURPOSE Over one million American firefighters are routinely exposed to various occupational hazards agents. While efforts have been made to identify and reduce some causes of injuries and illnesses among firefighters, relatively little has been done to evaluate and understand occupational noise exposures in this group. The purpose of this pilot study was to apply a task-based noise exposure assessment methodology to firefighting operations to evaluate potential noise exposure sources, and to use collected task-based noise levels to create noise exposure estimates for evaluation of risk of noise-induced hearing loss by comparison to the 8-hr and 24-hr recommended exposure limits (RELs) for noise of 85 and 80.3 dBA, respectively. METHODS Task-based noise exposures (n=100 measurements) were measured in three different fire departments (a rural department in Southeast Michigan and suburban and urban departments in Northern California). These levels were then combined with time-at-task information collected from firefighters to estimate 8-hr noise exposures for the rural and suburban fire departments (n=6 estimates for each department). Data from 24-hr dosimetry measurements and crude self-reported activity categories from the urban fire department (n=4 measurements) were used to create 24-hr exposure estimates to evaluate the bias associated with the task-based estimates. RESULTS Task-based noise levels were found to range from 82–109 dBA, with the highest levels resulting from use of saws and pneumatic chisels. Some short (e.g., 30 min) sequences of common tasks were found to result in nearly an entire allowable daily exposure. The majority of estimated 8-hr and 24-hr exposures exceeded the relevant recommended exposure limit. Predicted 24-hr exposures showed substantial imprecision in some cases, suggesting the need for increased task specificity. CONCLUSIONS The results indicate potential for overexposure to noise from a variety of firefighting tasks and equipment, and suggest a need for further exposure characterization and additional hearing loss prevention efforts. RELEVANCE TO INDUSTRY Firefighters may be at risk of noise-induced hearing loss, which can affect their fitness for duty and ability to respond effectively to emergencies. The results of this study suggest that additional efforts at hearing loss prevention among firefighters are warranted.

Injury Risk and Noise Exposure in Firefighter Training Operations

“…Firefighter training noise exposures were comparable to those we have previously documented in firefighting activity (Neitzel et al, 2013). Measurements from these and other studies (Kirkham et al, 2011; Tubbs, 1992) demonstrate the potential for exposure >85 dBA, the NIOSH recommended limit, suggesting increased risk of NIHL.…”

“…Noise exposures have not been well-studied among firefighters, but the limited existing data suggest that exposures may be widespread (Tubbs, 1995), specifically during emergency response and training operations (Kales et al, 2001; Neitzel et al, 2013). Neitzel et al (2013) demonstrated potential for exposure >85 dBA, the full-shift Time-Weighted Average (TWA) limit recommended by the US National Institute for Occupational Safety and Health (NIOSH), and found that the highest levels were associated with saws and pneumatic chisels (Neitzel et al, 2013). For reference, 60 dBA is approximately as loud as normal speech at arm's length, 85 dBA is about as loud as a gasoline-powered lawnmower, and 100 dBA is roughly as loud as a motorcycle.…”

Twenty-four-hour work shifts, increased job demands, and elevated blood pressure in professional firefighters

“…Firefighters can be exposed to a short-term, high level of noise during their emergency operations (e.g. sirens and using extraction equipment) (Neitzel et al 2013). However, we observed during the current study that firefighters regularly wore headsets with a dual function of noise protection and internal communication on fire trucks and engines when they responded to calls.…”

Double Jeopardy

“…These self-reported noise exposures are congruent with the literature. Neitzel et al (2013) reported that firefighter task-based noise levels ranged from 82 dBA to 109 dBA, and the majority of estimated 8-hour and 24-hour noise exposures exceeded recommended exposure limits. Root et al (2013) also found that commonly used fire station equipment (i.e., lawn maintenance equipment, snow blowers, compressors, and emergency alarms) and equipment on the fire engines (i.e., fans, saws, alarms, and extrication equipment) emitted noise equal to or greater than 85 dBA.…”

“…Firefighters are routinely exposed to occupational noise from a variety of firefighting tasks and equipment, such as the use of saws and pneumatic chisels (Neitzel, Hong, Quinlan, & Hulea, 2013). Construction workers in the operating engineer trade are also exposed to a noise level above 85 dB (loud enough to cause hearing loss) when they operate heavy equipment (e.g., bulldozers, graders, backhoes, asphalt road rollers, asphalt spreaders, and wheel loaders; Kerr, Brosseau, & Johnson, 2002; Legris & Poulin, 1998).…”