Hearing loss is an occupational disease under section 13(u) of Regulation 84-66 of the WC Act when it is caused by industrial trauma or noise induced due to excessive levels of noise in the workplace. Eligibility for compensation is based on whether the personal injury by accident (hearing loss) arose out of and in the course of employment.
When WorkSafeNB is satisfied the hearing loss was not caused by employment in New Brunswick, no compensation is paid. [ss 85(2) WC Act].
Hearing loss from aging is not work-related. It does not arise out of and in the course of employment as required by law, and therefore no benefits can be paid.
Persuasive Evidence of Occupational NIHL
a) It is sensorineural;
b) Hearing loss is usually in both ears, unless there is evidence of unilateral exposure;
c) Its first sign is a notching of the audiogram at high frequencies of 3000, 4000, or 6000 Hz with recovery at 8000. The hearing test must be performed at all frequencies from 250 to 8000 hertz.
d) It almost never produces a loss greater than 75 decibels in high frequencies, and 40 decibels in lower frequencies.
Permanent Physical Impairment
“The Merck Manual – 2nd Home Edition”, Merck Research Laboratories, 2003.
ISO 1999-1990. Acoustics - Determination of occupational noise exposure and estimation of noise-induced impairment. Internat. Standard ISO 1999. 2nd ed. Geneva, 1990.
American College Of Occupational And Environmental Medicine (ACOEM). “ACOEM Guidance Statement: Occupational noise-induced hearing loss.” JOEM 54, 1 (January 2012): 106-108.
ACOEM – the American College of Occupational and Environmental Medicine represents more than 4,500 physicians and other health care professionals specializing in the field of occupational and environmental medicine; dedicated to promoting the health of workers through preventive medicine, clinical care, research, and education.
Attributable Risk Fraction - is a figure derived from the overall strength of association and is a measure of the proportion of cases of the disease that are reasonably attributable to the exposure.
Decibel “dB” – a unit for expressing the relative intensity of sounds on a scale from zero for the average least perceptible sound to about 130 for the average pain level (Webster’s Collegiate Dictionary).
Decibel(A) “dB(A)” – levels of dBs weighted according to the weighting curves to approximate the way the human ear hears.
Noise-induced hearing loss (NIHL) - a permanent decrement in hearing threshold levels (HTLs), with a characteristic reduction of hearing sensitivity at the frequencies of 3, 4, and/or 6 kHz, and relatively better hearing sensitivity in surrounding frequencies, i.e., 2 or 8 kHz (WHO).
Sensorineural hearing loss – hearing loss due to damage to the sensory structures (hair cells) of the inner ear, auditory nerve, or auditory nerve pathways in the brain (Merck Manual).