Measurements taken by the Occupational Health and Safety Service show that at a speed of 80 km/h the sound level under the helmet is over 90 decibels. Speed has a significant effect on the sound level the driver or rider is exposed too. For each 18 km/h increase in speed, the intensity of the sound is doubled.
This means that at just over 100 km/h the driver or rider is exposed to approximately the same level as a circular saw operator who would not be allowed, by law, to operate the equipment without the mandatory use of hearing protection.
Using the government noise regulation figures implemented for the workplace, the safe exposure time relative to riding a motorcycle or racing in an open-topped car at certain speeds are as follows:
|Speed (kmh)||Noise Level||Safe Riding Time||
With 15db Protection
|80||91||3 hours||64 hours|
|102||94||1 hour||32 hours|
|120||97||30 minutes||16 hours|
|138||100||15 minutes||8 hours|
|158||103||7.5 minutes||4 hours|
|177||106||3.75 minutes||2 hours|
All of the noise levels indicated above exceed the point at which hearing protection MUST be worn in a working environment.
Noise induced hearing loss is permanent and irreversible. Adequate protection of the hearing mechanism is as important as the use of a helmet and protective clothing.
Conventional foam and wax earplugs can be a solution but are often uncomfortable to wear and isolate the user from their surroundings too much. Alternatively if not inserted properly they provide little or no protection.
Custom made hearing protection provides an individual and unique fit for the user allowing guaranteed levels of protection and comfort.