Introduction

Since noise pollution cannot be seen or felt, most of us do not consider it a severe threat. But with a rising population and rapid urbanization, we can no longer ignore the problem. Noise pollution has the potential to cause just as much harm as air and water pollution does. The government and constitution of India have set aside provisions for the prevention and control of noise pollution to protect people from it.

1. There are sections in the Code of Criminal Procedure that allow magistrates to eliminate irritants. In this case, the irritant can be noise pollution. This law enables the removal of noise-causing pollutants from public and residential spaces. The noise pollutant could be any source that produces a loud noise.
2. The Indian Penal Code has various sections that deal with ‘public nuisances.’ Some sections also deal with the responsible use of machinery. These laws protect a person’s right to a peaceful environment. Suppose noise becomes an everyday nuisance and harms mental and physical health. In that case, a citizen can approach a court, and the court will direct authorities to take necessary action against the perpetrators.
3. The Noise Pollution Control Rule, 200 strictly specifies the sound levels to be maintained around industrial, commercial, and residential areas.

Control of Noise at Source

Individuals and organizations can control noise in several ways. Noise controls measures differ according to the environment and the source generating noise. Individuals, employers, and businesses can use the following controls to reduce the impact of noise pollution on human health and the environment.

1. Elimination: Elimination involves the removal of noise at the source. Examples of elimination include not using machines that generate noise, moving noisy activities away from other silent activities, outsourcing the noisy work, and preventing the impact of hard objects on surfaces. Those that own construction businesses can most effectively implement these measures at construction sites. They protect a construction worker’s hearing ability. They also do not allow people living around construction sites to be affected by noise.

2. Substitution: Substitution involves replacing noisy machines or activities with quieter ones without changing the quality of the work done. We use substitution when we cannot eliminate it. For example, instead of hammering a nail to join two objects, people can consider gluing those surfaces.

3. Engineering: Engineering involves making physical changes to an activity, machine, or room. These changes reduce the noise exposure of workers and people living around typically noisy areas. Examples include separating the noisy area by a sound-proof barrier and putting up sound-absorbing material on windows and walls.

Control of Transmission

Noise can be controlled during its transmission or propagation by:

1. Putting up obstacles like barriers or enclosures in the noise transmission path.
2. Using mufflers that dissipate noise in all directions rather than having the concentration of noise at one place. Dissipation of noise causes a loss in noise intensity, thereby ensuring a safe noise exposure of people.
3. Secondary controls, such as white noise, can block or significantly decrease the level of noise reaching a receiver.

Protection of an Exposed Person

Eliminating all sources of noise pollution in everyday life is impossible. But if you feel like you are being exposed to an unsafe level of noise regularly, take the following steps:

1. If your work involves continuous exposure to noise greater than 85 dB, wear earplugs.
2. Avoid taking up a job that involves exposure to hazardous noise levels. However, make sure that your employer knows the risks and provides you with hearing protection if you have to.
3. Consider moving to another place with less traffic and not around industries if you are living in a noisy environment.
4. If your job already involves exposure to high noise levels, prevent using headphones/earphones at high volumes. Your headset volume should not be more than 60% of the maximum volume. Do not use your headset for a long time. Taking periodic breaks can give your ears rest.

Noise Pollution Analyzer

Employers and the general public can use a noise meter or sound level meter to analyze noise pollution in an area. These instruments are suitable for any environment. However, they are mainly used to study industrial and aircraft noise and noise in workplaces. Employers use it in offices to gauge employees’ stress levels and make necessary changes in the working environment. Reducing noise pollution in offices can create better working conditions for workers. Workers can also benefit from reduced hypertension and sleep disorders.

A noise analyzer commonly detects noise levels over a typical working day. i.e., 8 am to 10 pm. In recent years, an increase in noise pollution has made it important to analyze noise in different environments. Noise analyzers have made it extremely easy to identify sources of noise pollution and effectively control them.

Anti-Noise Devices

Anti-noise devices use secondary sounds to cancel out unwanted noise. Sound waves make up sound. Anti-noise devices emit sound waves out of phase with the sound waves of noise. These two waves interfere with each other and cancel each other out. Thus, the device can attenuate loud background noises.

Today, anti-noise devices have circuits and digital processors installed in them. The design of these elements automatically detects background noise and its amplitude. It then generates a signal with the same amplitude to cancel it out. The signal generated is amplified, reducing the level of the noise.

People usually place anti-noise devices (usually anti-noise speakers) at the exact location as the noise source for their effective attenuation. However, these devices are often suitable only for indoor, enclosed environments. They are not the best option to reduce noise in public open spaces. If used in public places, the results could be disastrous. The wavefront of the noise source and the wavefront of the device can match and create alternate zones of low and high-intensity noise.