Characterization of Noise Pollution from Construction 

Construction and building sites are among many sources of noise pollution. Most of the noise from construction sites is hazardous. Noise emanates from the use of equipment in construction activities. The activity at a construction site is constantly changing as the work progresses. There may be carpentry work, welding, cementation, mason work all going on simultaneously. There is a specific set of equipment used for each job. Therefore, characterization of noises from construction work can vary. Also, workers performing seemingly quiet tasks can be exposed to loud noises from workers performing other tasks around them. Below mentioned are some common construction tasks workers perform along with the average noise level they generate.

1. Electricians – 96 dB
2. Welding – 98 dB
3. Masonry – 100 dB
4. Bulldozing – 100 dB
5. Engineers – 98 dB
6. Cementation – 103 dB

Noise at a construction site is difficult to control since the tasks’ location is constantly changing. There are also constant adjustments being made to the size of building features making construction sites a hazardous source of noise pollution. 

Equipment and instruments like drills, cement mixers, welding machines, saws, jackhammers, cutters, and dumping trucks generate high levels of noise. These noise levels go beyond the limits for safe hearing. They may be generated in short pulses of high intensity, or they may be continuous. 

Most employees at construction sites refrain from wearing noise protectors saying that they make working conditions uncomfortable. When hearing noise protectors, they cannot hear fellow workers, they would not be aware of warning signals, and they feel hot. Some workers are even unaware of the risk they put their hearing at and the need for noise protectors. These issues must be solved to protect the hearing of construction workers. Employers must conduct training programs to make workers aware of the on-site hazardous noise levels. 

Characterization of Noise Pollution from Mining, Transportation, and Industrial Activities

Mining involves heavy use of machinery. The machines are always in continuous use. Their use in various activities generates high levels of noise. Noise pollution at mines is a significant health hazard. It affects millions of mine workers and people living in residential areas around the mines. Many mineworkers suffer from stress, sleep disorders, and noise-induced hearing loss. People living around mines also suffer from similar conditions, albeit to a lesser extent. An acoustic barrier must be installed on the perimeter of mines to attenuate noise. The two common methods for assessing noise levels in mines are noise dosimetry and a sound level meter. 

Road transport is the dominant source of noise pollution that affects all living beings. Most noises from road traffic cross the safe limit of 55 dB during the day and 50 dB during the night. Railways are the second dominant source of noise pollution. People living around railway tracks are exposed to noise levels above 55 dB daily, causing great harm to their health. 

Plants and factories are the primary sources of industrial noise pollution. Noise from industries can affect those working in the industry and those living around it. Workers in the steelwork industry are prone to the highest levels of industrial noise pollution. Steelwork involves using industrial blowers that generate noise levels of higher than 110 dB. It causes hearing and speech impairment among industrial workers. The sources of noise pollution that cause the most damage in an industrial setting are:

1. Machinery
2. Vehicles 
3. Construction

Apart from destructive hearing effects, noise from these sources can lead to psychological trauma too. Workers involved in these activities must wear appropriate protective gear to avoid damage to their physical and mental health. 

 Airport Noise

People living around airports are exposed to more than 70 dB of noise daily. As the tourism industry boomed, communities living peacefully near airports were suddenly exposed to high noise levels that resulted from increased air activity. People became annoyed and irritated by increased landings, take-offs, and the construction of new runways. A survey found that hypertension and hearing impairment was common among people living around airports. There was a 10-20% increase in the chances of people being hospitalized due to a heart attack or stroke. 

Airport administrations now put up noise barriers and offer compensation to residents. They also offer application forms for locals to submit complaints. An increase in runway usage and air traffic was the reason for most complaints. 

The primary source of noise pollution from airports is the aircraft engine. However, the good news is that: with advancements in technology, engine noise has been reduced. Aircrafts today generate 50% less noise compared to when they first started. Even so, there is much more air traffic today than ever before. Although engines were very loud a few decades ago, fewer aircraft were being operated, unlike now. Therefore, locals do not consider reducing engine noise a significant improvement in curbing noise pollution from airports. 

The noises from airports also have adverse effects on animals and wild species. The noise and movement of aircraft affect the migratory patterns of birds. They also damage hearing and interfere with the survival of other species living in ecologically sensitive zones around airports. 

There is a requirement for major advancements in technology that can effectively reduce engine noise, considering the amount of air traffic. Governmental authorities should also be strict in ensuring that airports are operated far away from residential and ecologically sensitive areas. 

General Control Measures

The following measures can help effectively control noise pollution.

1. An improvement in the design of machines to make them quieter but with the same work efficiency. 
2. Regularly carrying out a maintenance check of machines. 
3. The construction of soundproof chambers around noisy machines. 
4. Wherever applicable, a sound absorber can cover the noise-producing part of a machine. 
5. The designation of silent zones around schools, residential areas, and hospitals. 
6. Ensuring that bus and railway terminals, airports, industries are constructed on lands that are situated away from residential and forested areas. 
7. Filling the windows in upcoming buildings with triple glass panes and material that absorbs outdoor sound can reduce the noise. 
8. Creating a green barrier by planting trees around the noise source can significantly attenuate noise. 
9. White noise can be generated to mask loud background noise. People usually use white noise to help them fall asleep.
10. There should be strict legislative rules that prevent noise after or before a specific time. For example, in some areas, loudspeakers and amplifiers are banned after 10 pm.