Noise: The Invisible Hazard. WHAT IS NOISE? WHAT ARE THE EFFECTS OF NOISE? WHY MORE STRESS ON NOISE?

Noise: The Invisible Hazard

WHAT IS NOISE?WHAT ARE THE EFFECTS OF

NOISE?

WHY MORE STRESS ON NOISE?

Did you know......noise is the most common hazard? ...hearing loss from noise is slow and

painless; you can have a disability before you notice

it? ...hazardous noise is found off the job

from things like power tools, lawn mowers and guns?

...you can protect yourself from hazardous noise?

Noise is often defined as undesired or unwanted sound or sound without agreeable musical

quality.

BUT, this definition is subjective

because of the fact that one man’s sound is other man’s

noise, so we can define noise in a better way as :

Noise is “wrong sound in wrong place at wrong time.”

Sources of noise: They are many and varied:

AutomobilesFactoriesIndustriesAircrafts

Domestic like TV , coolers , mixies etc .all adding to the

quantum of noise in daily life.

Effect of noise on ears:They are of two types:--

Non-auditory.Auditory

NON-AUDITORY EFFECTS:Interference with speech

Communication: Annoyance:

EFFICIENCY: FATIGUE:

PHYSIOLOGICAL EFFECTS

PHYSIOLOGICAL EFFECTS Rise in B.P,

Rise in intra cranial pressure, Increase in heart rate,

Breathing, Sweating,

General symptoms like giddiness, Nausea may also occur.

Noise interferes with sleep.

AUDITORY EFFECTS:It appears in the 90db.region and is

greatest at 4000Hz,may be associated with whistling and

buzzing in the ears.

The most serious pathological auditory effect is DEAFNESS or

hearing loss.

This loss can be:TemporaryPermanent

Repeated or continous exposure to noise around 100 db may result

in permanent hearing loss.Exposure to noise above 160db

may rupture tympanic membrane that leads to permanent loss of

hearing.

Every person responds differently to noise.

ROUTINE NOISE LEVELS IN DECIBLES:

Whispering 20-30db.Slow and soft music 40-50db.Normal conversation 60-65db.

Heavy traffic 80db.Air -plane 120db.Jet engine 140db.

COMMERCIAL NOISE LEVELS IN DECIBLESType writer 80db.

Lathe machine 85db. Fabrication workshop 100db.

Drill machine 110db.Blasting 110db.

ACCEPTABLE NOISE LEVELSResidential:

Bedroom 25db.Living room 40db

Office 35-45db.Conferences 40-45db.Workshop 40-60db.Laboratory 40-50db.Class room 30-40db.Library 35-45db.

Hospital wards 20-35db.

A daily exposure up to 85db is above the limit people can tolerate without substantial damage to their hearing.

SAFE ZONE UP TO 85db DANGER ZONE 90-120db.DANGEROUS ZONE >120db.

Common sounds may be louder than you think...

Factors affecting injury to ear due to noise exposure:

IntensityFrequency range

Duration of exposureIndividual susceptibility

NOISE CONTROLControl of noise at source

Control of transmission:- this maybe achieved by:

Building enclosures.

Covering the room wall and floor with sound absorbing material.

Protection of exposed persons:-

Employees must be regularly rotated from noisy areas.

-Periodic audiogram checks .-Use of ear plugs /muffs are

also essential

No noise abatement programme can succeed

without people’s participation.

The main aim of this information is to motivate people against noise pollution in their daily living activities and lead an

improved quality of life.

THANKS