Noise effect on human health

1. KARUNA
LAGGERI
NOISE

2. DEFINITION
 Wrong sound in the wrong place, at wrong time.
 In 20th century has been described as century noise
 It has become very important stress factor.

3. Sources

4. sources
 Auto mobiles
 Factories
 Industries
 Aircrafts
 Noise level are particularly acute near railway
junctions, traffic round about, bus terminuses and
airports.
 Recreational noise of loudspeakers with full volume
of noise production.
 Domestic noises from Radios, T.V

5. PROPERTIES
1. Loudness
2. Intensity and frequency

6. LOUDNESS
 The loudness of noise is measured in decibels.
 Normal conversation produces a noise of 60-65 dB
 Whispering 20-30dB
 Heavy street traffic 60-80dB
 Broiler factories about 120dB
 A daily exposure up to 85dB

7. Frequency
 The frequency denoted as Hertz(Hz)
 One Hz is equal to one wave per second.
 The human ear can hear frequencies from about
20-20,000 Hz.

8. Effects of noise exposure
 The effects of noise exposure are two types:
 Auditory
 Non auditory

9. AUDITORY EFFECTS
 Auditory fatigue: whistling and duzzing
 Deafness: hearing loss may be temporary or
permanent.
 The disability disappears after a period of time up
to 24 hours following the noise exposure.
 Most hearing loss occurs in frequency range b/w
4,000-6,000Hz.
 Repeated or continuous exposure to noise
around 100 decibels may result in a permanent
hearing loss.

10. NON AUDITORY
 Interference with speech
 Annoyance
 Efficiency
 Physiological changes: Rise in BP, ICP, HR,
breathing, sweating.
 General symptoms such as nausea, giddiness and
fatigue, sleep disturbances, reduce color perception
and night vision.

11. CONTROL OF NOISE
 Careful planning of cities
 Control of vehicles
 To improve acoustic insulation of building
 Industries and railways
 Protection of exposed persons
 Legislation
 Education