IT is common to see police vehicles unnecessarily using sirens — also called hooters — from morning till late in the night. The problem is severe at Teen Talwar, Ch. Khaliquzzaman Road, Punjab Chowrangi and Schon Circle. What is the point of using sirens early on Sunday mornings?

These sirens’ sound levels peak at 120 dB(A) — decibels on A-weighted scale which is detrimental to the health of citizens as well as police personnel.

Epidemiologic studies show that environmental noise is associated with an increased incidence of arterial hypertension, myocardial infarction and stroke.

A 1974 US Environmental Protection Agency document ‘Information on Levels of Environmental Noise Requisite to Protect Public Health and Welfare with an Adequate Margin of Safety’ suggests noise level of 70 decibels to protect public health and welfare against hearing loss, annoyance and activity interference. Noise levels of 45 decibels are associated with indoor residential areas, hospitals and schools. Noise levels of 85 dB(A) and greater, cause a host of health problems, including hearing loss.

A World Health Organisation report issued in 2000 states that noise accelerates and intensifies the development of latent mental disorder.

According to the American Speech-Language-Hearing Association, sounds at 85 dB(A) can lead to hearing loss if exposed for more than eight hours at a time.

A recent study reveals that transportation noise is associated with myocardial infarction (medical term for heart attack) mortality.

A reputed American medical journal says excessive noise leads to aggressive behaviour, anger, depression, anxiety, fear, irritation, and tension. Recent research reveals a significant relationship of community noise with breast cancer, stroke, type 2 diabetes, and obesity.

The American Centres for Disease Control and Prevention, say noise can damage sensitive parts of the ear, causing hearing loss, ringing or buzzing in the ear and increased sensitivity to sound . Noise above 70 decibels over a prolonged period of time may damage hearing. Loud noise above 120 decibels can cause immediate harm to ears.

A one-time exposure to extreme loud sound or listening to loud sounds for a long time can cause hearing loss. Loud noise can damage cells and membranes in the cochlea. Damage to the inner ear or auditory neural system is generally permanent.

There is no medical or surgical treatment for hearing loss caused by noise. Traffic policemen should be alarmed that if sirens don’t bother them, they may already have some hearing damage.

F. H. Mughal
Karachi

Published in Dawn, January 6th, 2020