Noise Control Knowledge for the Uninitiated

Sound is necessary in our daily life while noise is unwanted sound. Any unwanted sound that makes people have difficulty in hearing is noise.

Noise is everywhere and it exits in residential, commercial and industrial areas such as schools, office buildings recreational activities, car electronics, production lines, planes, machinery, mining transportation etc. Overall, noise is a result of our mechanical and electronic civilization, which can be anything from quiet, to annoying to loud and harmful.

Impact of noise in daily life

Extreme noise is very harmful and it can kill plants and destroy animals. Loss of hearing is the most common result for human beings who suffer from excessive noise.

Noise such as loud music can cause hearing loss before you reach 30 years old. Researchers have proved that many side effects can result from noise. That noise causes epileptic seizures, increases blood pressure and arises heart disease, stress, sleep deprivation, interference with concentration, murder, suicide and vision problems.

To reduce noise to the level we can stand, airport curfews have been implemented, truck’s using exhaust brakes in suburban areas have been restricted so we can relax and sleep.

Impact of noise in the workplace

In the Australian standards, noise is defined as “all sound (in the workplace) whether wanted or unwanted” and is usually known as “Occupational Noise”. Blue collar workers, tradesmen, labourers and machine or plant operators are the common groups that are affected by noise.

Noise control is now a main concern amongst manufacturing managers and operational managers since the new Government WH&S regulations have been implemented. Acoustical engineering has become an industry of its own, with industry associations and university departments being established. Medical practises now specialise in pre-employment medical examinations with hearing tests.

Indication of noise

Usually when a person has to raise his voice to talk to someone who is about an arm’s length away, it is an indicator that the noise maybe hazardous.

Decibel (dB) is a logarithmic unit used to express the ratio between two values of a physical quantity, often power or intensity. 0 dB upward towards the threshold of pain, about 120-140 dB. For example, the sound level in a whisper quiet library is 30 db, average residential home is about 40 dB, average conversation is about 60 dB, typical home music listening levels are about 85 dB, a loud rock band about 110 dB, and a jet engine close up could be 150dB. See the Decibel (Loudness) Comparison Chart.

Acoustic Engineering

Acoustic engineering is a type of engineering that deals with sound and vibration. Acoustic Engineers are typically concerned with the design, analysis and control of sound. There are different specialists in numerous areas of expertise e.g. Commercial Acoustics, Industrial Acoustics, Architectural acoustics, Marine Acoustics, Musical Acoustics, Bioacoustics, Electro Acoustics and Medical Acoustics.

The main goal of acoustic engineering is to control noise, which is to reduce unwanted noise. Noise control could be implemented in a variety of ways including redesigning sound sources, the design of noise barriers, sound absorbers, silencers, and buffer zones, and the use of Personnel Protective Equipment (PPE) hearing protection devices (Earmuffs or Earplugs).

Take Actions

It is crucial to understand the difference between sound and noise and the impact of noise that it has on human beings and animals. When noise exceeds the safety level in the environment, necessary action is required. To test the noise level in the environment and reduce the noise to a level that does not harm people and animals, acoustic consultants/engineers will design solutions for you and acoustic product manufacturers will tailor specialised acoustic products to keep your environment safe.