Noise is generally viewed as one of a number of general biological stressors. It is felt that excessive exposure to noise might be considered a health risk as noise may contribute to the development and aggravation of stress related conditions such as high blood pressure, coronary disease, ulcers, colitis, and migraine headaches. Loud sounds, such as impact noise and explosions, can cause an arousal response in which a series of reactions occur in the body.
Sound is a form of energy like electricity and light. Noise, however, is unwanted sound which cause pain and annoyance. Nevertheless, no one on earth can escape the sound of noise or an unwanted, disturbing sound. Every day we experience different types of noise. Road traffic, garbage trucks, jet plains, construction equipments, manufacturing process, lawn mowers, and boom boxes, are among the audible litter that are consistently broadcasted in the air.
According to McDonald, there are three broad types of industrial noise - wide band noise, narrow band noise and impulse noise. Wide band noise is noise that is distributed over a wide range of frequencies. Most noise from manufacturing machines is wide band noise. Narrow band noise is noise that is confined to a narrow range of frequencies. The noise produced by power tools is narrow band noise. Impulse noise consists of transient pulses that can occur repetitively or no repetitively. The noise produced by a jackhammer is no repetitive impulse noise.
There are numerous effects on the human environment due to the increase in noise pollution. Noise causes hearing loss, interferes with human activities at work and home, and is in various ways dangerous to people's health and well being. In addition to hearing loss, there is evidence that excessive noise can cause other physiological problems. Apart from that, quickened pulse, increase blood pressure, constriction of blood vessels and heart disease can be caused by the excessive noise.
Look! How dangerous noise is! However noise can be reduced by engineering or administrative controls. The best noise control is reducing noise at the source. The second priority is to reduce noise along its path. If there is a problem in reducing noise with this method, using personal protective deceives can help us in noise reduction at the receiver.
Sound and vibration are very similar. Sound typically relates to a sensation that is perceived by the inner ear as hearing. Vibration, on the other hand, is inaudible and is perceived through the sense of touch.
The types of injuries associated with vibration depend on its source. Some can lead problems ranging from motion sickness to spinal injury while others blood vessels.
On the whole, vibration hazards are closely associated with noise hazards because tools that produce vibration typically also produce excessive levels of noise. Therefore the strategies for protecting employees against the noise associated with vibrating tools are the same as those presented.
Conclusions concerning the factors that determine an individual's subjective, psychological response to noise are difficult to derive since individuals vary so much in their reaction to noise. Clearly, more research is needed to assess this complex topic fully.
Excessive noise exposure can bring about a wide variety of psychological responses or
symptoms in the individual. A person may respond with anger, or experience symptoms such as anxiety, irritability, and/or general emotional stress. Distraction and poor judgment may result from mental fatigue.
The physical attributes of noise that can affect an individual's subjective response include: apparent loudness or intensity, spectral shape, presence of discrete frequency components, abruptness or impulsiveness, intermittency, duration, and temporal variations.
Among the factors that affect an individual's response to noise are contextual factors such as: the
time of day, the activity interfered with, the ability to control the source, and the information content of the noise. Response may also be affected by personal factors such as previous experience with noise exposure or socio-economic and educational status.
With respect to industrial noise at or inside a residence low frequency noise of 250 KHz or lower (especially those with discrete frequency components) are generally the most annoying and disruptive, although noises that are abrupt, intermittent, or fluctuate with time can be very annoying as well. In general, the louder the noise the more annoying it is likely to be.
When it comes to health effects related to noise annoyance levels it is clear that these are very difficult to quantify given the many factors that influence the outcome. By understanding both the Technical and Psychological factors that affect "Annoyance" we are able to categorize the parameters that must exist for it to manifest itself in those living near industrial facilities. Addressing the Annoyance factors meaningfully in the planning, design and operational stages, will help to minimize Annoyance from occurring in the first place and secondly provide the foundation for a lasting relationship between the operator and their neighbours built on mutual trust and respect.