The National Safety Council has chosen hazard recognition as the theme for the final week of National Safety Month.

Sudden, occasional or continuous noise is a prevalent workplace exposure hazard in need of recognition. Noise-induced hearing loss is a commonly occurring occupational illness that can be prevented with consistent use of correctly fitted hearing protection such as earmuffs, ear plugs or caps.

Temporary or permanent hearing loss impacts safety, health and quality of life. Severe hearing loss is associated with $300,000 in societal costs over a person’s lifetime, with 67 percent of that amount attributed to lost productivity.

Noise-induced hearing loss limits the ability to hear high-frequency sounds and speech. Lack of protection from noise above a certain decibel level:

• Contributes to fatigue and physical and psychological stress
• Affects concentration and productivity
• Interferes with socialization and communication
• Increases risk of accidents and injuries
• May be a cardiovascular health risk factor

Exposure Risk

An estimated 22 million U.S. employees are exposed to potentially hazardous noise levels at work. In surveys, more than 50 percent of noise-exposed workers have reported not wearing hearing protection, according to the National Institute for Occupational Safety and Health. In addition, unrelated to noise, an estimated 10 million workers are at risk of exposure to ototoxic chemicals that can damage hearing.

Even more Americans are exposed to potentially damaging noise in their daily lives. Commonly encountered noise generators include gardening and carpentry tools; various modes of transportation, traffic congestion and vehicle horns; construction and farming equipment; machinery in manufacturing facilities; firearms; and loud music.

The Occupational Safety and Health Administration (OSHA) requires covered employers to establish a comprehensive hearing conservation program when workplace noise exposure ratings are equal to or greater than 85 dBA during an eight-hour workday in general industry and 90 dBA over eight hours in the construction industry. By comparison, the World Health Organization recommends less than 40 dB as an annual average of night-time noise outside a bedroom window to prevent negative health effects, and less than 30 dB of noise inside bedrooms for high-quality sleep, according to a New York Times article published on June 9. (The difference between dB and dBA is that dB sound pressures are unweighted, while dBA-weighted levels are based on the relative loudness of sounds intercepted by the human ear.)

The New York Times article, Noise Could Take Years Off Your Life, cites research that indicates repeated exposure to outside noise, such as loud traffic, increases the likelihood of hypertension, stroke and heart attacks for more than 100 million Americans. Noise above a certain level activates the amygdala, a section of the brain that triggers the endocrine system to release cortisol, adrenaline and other chemicals in the body. This response may also initiate a sympathetic nervous system reaction that raises heart rate, increases blood pressure and produces inflammatory cells.

“When researchers analyzed the brain scans and health records of hundreds of people at Massachusetts General Hospital, they made a stunning discovery: Those who lived in areas with high levels of transportation noise were more likely to have highly activated amygdalas, arterial inflammation and — within five years — major cardiac events,” the New York Times reported.

Hearing Tests

In workplaces with noise exposure hazards that cannot be reduced to safe levels with engineering or administrative controls, OSHA requires hearing tests to establish a baseline and repeat testing to measure potential hearing loss over time. Under any circumstances, a medical professional should check hearing when there are warning signs such as:

• Turning up TV, radio, phone or music volume because of difficulty hearing
• Frequently asking people to repeat what they have said or feeling as if they are mumbling
• Avoiding social interaction, reading lips, interrupting or making inappropriate comments
• Inability to hear environmental sounds others can hear, such as birdsong or rain falling
• Hearing ringing, buzzing or muffled sounds, which are signs of tinnitus

A hearing test, or audiogram, is typically conducted by a qualified professional in a lab, sound-proof room or booth in a clinic, mobile medical unit, school or workplace. WorkCare provides a comprehensive hearing conservation program that features onsite, mobile or off-site audiometric testing at preferred provider locations, medical monitoring by occupational health physicians, and exam scheduling, results tracking and recordkeeping.

For onsite testing, WorkCare clients have the option to use a clinically validated, portable audiometer that complies with OSHA, American National Standards Institute (ANSI 23.6), U.S. Food and Drug