Noise Pollution
Noise consists of unpleasant obtrusive, annoying, distracting, or persistent sounds that interfere with sleep or the ability to concentrate or enjoy life. Thus, noise is unwanted sound. Noise is dangerous pollutant that is hazardous to health of a person. People creating noise beyond the deadline creates noise pollution.
Noise magnitude is often measured in decibels (dB), a logarithmic scale in which each increase of 10 dB corresponds to a 2-fold increase in magnitude. It is a unit for expressing the intensity of sound on scale from zero (for the average last perceptible sound) to about 130 from the average pain level. Even small values in dB levels means large differences in terms of sound pressure.
Sources of increasing ambient noise levels in public places:
- Industrial activity
- Construction activity
- Generator sets
- Loud speakers
- Public address systems
- Music systems
- Vehicular horns
- Other mechanical devices
Health Hazards due to noise pollutions
According to World Health Organisation (WHO) the effect of noise on the human system can range from annoyance to problems with communicating to actual physiological effects. “Noise above 80 decibels may also increase aggressive behaviour. It was pointed out by them that noise induced hearing impairment is the most common irreversible (and preventable) occupational hazard world wide. “Prolonged or excessive exposure to noise, whether in the community or at work, can cause serious permanent medical conditions like hypertension and ischemic heart disease. Noise can adversely affect performance, for instance reading, attentiveness, problem solving and memory”, states a fact sheet on occupational and community noise issued by the WHO.
For the sound sleep, WHO prescribes 30 decibels as the maximum continuous background noise and individual events should not exceed 45 dB. (Source: The Green Book Indian Evironmental Laws by P. B. Sahasranaman)
Health problems caused by noise pollution:
- Hearing loss or deafness
- High blood pressure
- Depression
- Irritability
- Fatigue
- Gastro-intestinal problems
- Allergy
- Distraction
- Mental stress
- Annoyance
- Ischemic heart disease
- Sleep disturbances
- Injuries
- Peptic ulcer
- Decreased work performance
- Affect communication
- Loss of efficiency
- Prolonged exposure to noise levels greater than 85 decibels can impair hearing permanently.
- Noise has following psychological effects –
- Annoyance
- Psychiatric disorders
- Adverse psychosocial well-being
Law in India
The Noise Pollution (Regulation and Control) Rules, 2000 (hereinafter referred to as “Noise Rules, 2000) has been enacted and enforced in India with the object to regulate and control noise producing and generating sources with the objective of maintaining the ambient air quality standards in respect of noise.
Noise Rules, 2000 are also applicable on hospitals. The Noise Rules, 2000 defines hospitals as an institution for the reception and care of sick, wounded, inform or aged persosn and includes government or private hospitals, nursing homes and clinics.
Ambient Air Quality Standards in respect of Noise of different areas / zones are:
| Area Code | Category of Area / Zone | Limits in dB(A) Leq | |
| Day Time | Night Time | ||
| (A) | Industrial Area | 75 | 70 |
| (B) | Commercial Area | 65 | 55 |
| (C) | Residential Area | 55 | 45 |
| (D) | Silence Zone | 50 | 40 |
Day time shall mean from 6:00am to 10:00 pm
Night Time shall mean from 10:00 pm to 6:00 am.
As per Noise Rules, 2000, silence zone means an area comprising less than 100 metres around hospitals, educational institutions, courts and religious places or any other place which is declared as such by the competent authority.
Thus, around hospitals the area is silence zone and the noise level in that area cannot be more than 50 dB during day time and 40 dB during night time.
Restriction on use of Loudspeakers / public address system
The Noise Rules, 2000 has put restriction on the use of loud speakers / public address system and the same cannot be used without written permission.
The loudspeakers / public address system / sound producing instruments / musical instruments cannot be used during night time except in closed premises for communication like auditoria, conference room, community halls, banquet halls or during public emergency.
Only on or during any cultural or religious festival of a limited duration not exceeding 15 days, the State Government may permit the use of loudspeaker / public address system during the night time between 10:00 pm to 12:00 midnight only
How to avoid / reduce noise pollution?
Ear plugs and ear muffs can be used for this purpose. The workers in noisy environment should be rotated to avoid prolonged exposure. Education about noise pollution and its health hazards are important steps.
Noise reduction: Several methods can be used to reduce night time noise exposure in the inpatient setting, including ear muffs or ear plugs for patients, sound masking (white noise), installing sound proofing acoustic materials, and behavioral modifications (“quiet time” protocols).
Patients report modest improvements in sleep with these relatively simple interventions.
Even though environmental noise reduction protocols typically only achieve small decreases in noise levels, subjective and observed sleep quality and duration appear to be improved.
