Industries having a high number of workers exposed to loud sounds include construction, agriculture, mining, manufacturing, utilities, transportation, and the military. In the United States, about 30 million workers are exposed to hazardous sound levels on the job, according to NIOSH. Other measures and definitions are used for other purposes. Mark Stephenson, a Cincinnati, Ohio-based senior research audiologist at the National Institute for Occupational Safety and Health (NIOSH), says his agency’s definition of hazardous noise is sound that exceeds the time-weighted average of 85 dBA, meaning the average noise exposure measured over a typical eight-hour workday. In its 1999 Guidelines for Community Noise, the World Health Organization (WHO) declared, “Worldwide, noise-induced hearing impairment is the most prevalent irreversible occupational hazard, and it is estimated that 120 million people worldwide have disabling hearing difficulties.” Growing evidence also points to many other health effects of too much volume. In fact, it’s difficult today to escape sound completely. During a single day, people living in a typical urban environment can experience a wide range of sounds in many locations, even once-quiet locales have become polluted with noise.
It’s not difficult for a person to encounter sound at levels that can cause adverse health effects. A decibel Hell (The Effects of Living in a Noisy World)