Noise is a major occupational hazard today. The most important disorder is hearing impairment, although hearing loss caused by sound is potentially preventable, Nevertheless, it is now considered one of the major health problems and one of the 10 major diseases caused by work. It is considered to be one of the major occupational diseases in Europe.
                      
 Noise-induced hearing impairment (NIHL) is an irreversible sensory impairment that is caused by prolonged exposure to noise. Drivers of heavy and semi-heavy vehicles are also prone to hearing loss due to long distances and continuous presence in road noise. Even mild hearing loss has difficulty listening to speech in background noise, identifying sounds, and locating sound sources and it can lead to dangers for drivers. Safe driving involves driver's ability to receive environmental messages through various senses, including hearing and interpretation, and compliance with them. Therefore, hearing will affect the effective communication of the driver. For example, the driver should be able to hear the sound of a nearby approaching car. Also, if the driver can hear sounds from a defect in the engine or the tire or other parts of the machine with the diagnosis of timely detection of possible defect, injuries and extreme events, such as accident occurrence is prevented. Continuous exposure to noise pollution of roads and heavy vehicles leads to significant driver hearing loss at 4 KHz frequency and surrounding frequencies. This requires the provision of regular auditory examinations, the provision of preventive strategies and changes in the lifestyle of this occupational group.

Collector: Fatemeh Salimi
References:

1. Moallemi M. Hajiabolhassan F. Assessment of hearing state in heavy and semi- heavy vehicle          drivers. J Rehab Med. 2014; 2(4): 31-36    
2. Sulkowski W, Szymczak W, Kowalska S, Sward-Matyja M, Area C. Epidemiology of
occupational noise-induced hearing loss (ONIHL) in Poland. Otolaryngol Pol. 2004;58(1):233-6