Noises
Noise is defined as an unwanted sound. It is one of the most present contaminants in the world of work.
Sound is produced by a series of pressure variations, in the form of vibrations, which spread through solids, liquids, gases (concrete, water and air, for example). These vibratory waves reach our ears and are interpreted as sound.
Evaluation:
The results of the measurements, compared to a benchmark, allow evaluating whether the concentrations found are harmful for health.
The evaluation criterion of noise is established by RD 1316/1989 on workers exposed to noise in the workplace.
The risk of hearing loss becomes significant from a daily level equivalent to 80 dB (A).
This hearing loss may be temporary or permanent and is associated with communication difficulties and behaviour changes.
There are other effects of noise in addition to hearing loss. Some people have shown breathing, cardiovascular, digestive or visual alterations. High noise levels can cause sleep disorders, irritability or fatigue.
Vibration
Exposure to vibrations occurs when the oscillating movement of a structure, including the floor, a handle or a seat is transmitted to a body part.
Vibrations can be of a very low frequency (the swinging of trains and rocking of ships cause travel sickness), low frequency (vehicles moving, forklifts trucks…, that have an effect on the inner ear and delay the reaction time) and high frequency (electric saws, jackhammers…, that have more serious consequences, such as articular and vasomotor problems in arms and legs).
Depending on how the contact between the vibratory object and the body is, the exposure to vibrations is divided into two major groups: hand-arm vibrations and general vibrations of the whole body.
