What is Noise?
Classification of Noise
Measurement of Noise
Causes & its Effect
What is Vibration?
Types of Vibrations
Causes & Effects of Vibration
Control of Vibrations
“Noise is any sound independent of loudness which can
produce an undesired physiological or psychological effect
in an individual.”
Word ‘NOISE’ derived from latin word ‘NAUSEA’ which
means feeling sickness
Noise is a type of sound which:i. Caries no information
iii. Undesirable & Unwanted
“Noise related to any occupation is called
Workers who operate, service or maintain
vehicles, equipments & machinery are exposed to
Ex- Cement & Concrete industries, Printing
press, Sheet Metal industries, Gear manufacturing
plants, Construction sites
MEASURMENT OF NOISE
‘DECIBEL’(dB) is used to measure the intensity of sound.
where I= sound intensity in watts/m2,
I0= reference sound intensity
Measuring Instruments :1.
SOURCES OF NOISE
1-Stationary Sources:- Iron & Steel plants, Textile mills, Printing
presses, Workshops, Metal Industries, use of loudspeakers on
festivals, Elections, Worships in Temples, Mosques etc
2-Mobile Sources:- Road traffic, Railway traffic, Aero traffic, Marine
vehicles, Agriculture machines
EFFCTS OF NOISE
a) Hearing impairment
c) Heart disease
d) Lowering the concentration and effect on memory
e) Muscular strain and nervous breakdown.
a) Depression and Fatigue
b) Mental Stress
d) Sleep Interference
Other Health Effects
a) Communication Disturbance
b) Habit of talking loudly
“Traffic noise alone is harming the health of almost
every third person in the WHO European Region.”
CONTROL OF NOISE
Noise can be controlled at three levels:
1. Reducing the sound produced.
2. Interrupting the path of the sound.
3. Protecting the recipient .
Noise can also be controlled by following:i. Reducing Impact Force.
ii. Reduce Speed and Pressure.
iii. Reducing Friction b/w Machine Parts.
iv. Isolate & Damper Vibrating Elements.
v. Providing Mufflers/Silencers.
vi. Highways could be routed away from populated areas.
vii. Maximum germination of green plants or vegetation.
Vibration is the mechanical oscillations of an
object about an equilibrium point. The
oscillations may be regular such as the
motion of a pendulum .
Vibration is desirable for the correct functioning
of the various devices in case of Harmoniums
While Vibrations are undesirable such as-
Creating unwanted sound noise
Vibration of engines, electric motors
TYPES OF VIBRATIONS
On the basis of force applied:-
Free vibration -Occurs when a mechanical system is set
off with an initial input and then allowed to vibrate
freely. Ex-simple pendulum
2. Forced vibration -When a time-varying disturbance
(load, displacement or velocity) is applied to a
mechanical system. Ex-shaking washing machine due to
an imbalance, transportation vibration (caused by truck
engine, springs, road, etc.),
On the basis of vibration expose
1. Hand Arm Vibration(HAV)When hand of a worker is
exposed to vibrating body
during the occupation.
2. Whole Body Vibration(WBV)when whole body expose to
vibrating body or system.
3. Environmental Vibration
CAUSES OF VIBRATION
Vibrations can be caused by i. Imbalanced rotating parts.
ii. Uneven friction.
iii. Meshing of gear teeth.
Vibration Exposure is caused in many occupations where
a worker is comes in contact with vibrating machinery or
i. Vibration enters the body from the organ in contact with
ii. Worker operates hand-held equipment.
iii. A worker sits or stands on a vibrating floor or seat.
EFFECTS OF VIBRATION
Effects of HAV
i. Vibration –induced White Finger(VWF)
ii. Hand Arm Vibration Syndrome(Raynauld’s
Effects of WBV
Anti Vibration Tools
2. Anti Vibration Gloves
3. Safe Work Practices
4. Employee Education