Mining industries: hearing loss prevalance and risk

New American research from the National Institute for Occupational Safety and Health (NIOSH) into the prevalence of hearing loss among noise-exposed oil and gas extraction and mining workers has found that as many as one in three workers are affected in some mining industries. The study, published online in July 2019, marks the first to examine hearing loss prevalence and risk by industry in the oil and gas extraction sector, and within most mining sector industries.

Researchers Sean M Lawson, Elizabeth A Masterson and Amanda S Azman found that across these sectors, at least 25% of workers experienced hearing loss, with that number exceeding 30% in some industries. The study examined audiograms for 1.9 million noise-exposed workers across all industries, including 1076 in oil and gas extraction and 9389 in mining. Across all sectors, a total of 16% of workers had hearing loss. This compared with 14% in oil and gas extraction and 24% in mining.

Oil and gas extraction

Within oil and gas extraction, other key findings included that those within national gas liquid extraction experienced a 28% incidence of hearing loss and faced a 76% higher risk of hearing loss compared with noise-exposed workers engaged as couriers and messengers. No data was available for drilling oil and gas wells and crude petroleum and natural gas extraction, two of the largest industries — indicating a need for greater worker surveillance.

Mining

In the mining sector — which accounted for 24% of noise-exposed workers — those in the construction sand and gravel mining industry experienced the greatest hearing loss (36%), which was followed in severity by uranium-radium-vanadium ore mining at 31%, bituminous coal and lignite surface mining at 28%, iron ore mining at 27% and copper ore and nickel ore mining at 24%.

Within this sector it was also found that workers in the gold ore mining industry faced a 71% higher risk of hearing loss compared with noise-exposed courier and messenger workers; workers in support activities for coalmining have twice the risk of hearing loss compared with couriers and messengers.

Significance

Noise exposure ranks as the primary risk for occupational hearing loss, with research indicating that 61% of all workers in oil and gas extraction and mining sectors have been exposed to hazardous workplace noise. Additionally, extant NIOSH research has shown that noise exposure is also associated with elevated cholesterol and high blood pressure.

“This study highlights the large proportions of workers with hearing loss and identifies the industries within these sectors that are most affected,” one of the researchers (Masterson) said of the study’s significance. “Occupational hearing loss is entirely preventable, and knowing which workers are at greatest risk can help better tailor strategies to protect their hearing.”

Preventing hearing loss

Where possible NIOSH recommends removing or reducing noise at the source or implementing a hearing conservation program in cases where noise cannot be reduced to a safe level. Engineering controls such as reducing equipment noise have shown promise in the mining sector, and should be developed and used whenever possible across sectors. Barriers to the use of hearing personal protective equipment (PPE) also need to be identified and eliminated, while the rotation of workers out of loud areas and away from noisy tasks to decrease exposure time is another critical hearing loss prevention measure. For more information from NIOSH on noise and hearing lost prevention, visit: www.cdc.gov/niosh/topics/noise.

The study, titled ‘Prevalence of hearing loss among noise‐exposed workers within the Mining and Oil and Gas Extraction sectors, 2006–2015’, was published in the American Journal of Industrial Medicine.

Image credit: ©stock.adobe.com/au/Michael Evans