PROPERTIES OF SOUND AND ITS MEASUREMENT
➢ Sound consists of wave motion in an elastic medium and caused by the vibrations of
molecules.
➢ It is the periodical mechanical disturbance in fluids and solids.
➢ Noise radiates from vibrating surfaces and from vibrating gases.
➢ Sound is produced in environment by alternating pressure changes in the air and is
caused by the vibrations of solid objects or separation of fluids over around or
through holes in solid objects.
➢ These vibrations cause surrounding air to undergo compression then rarefaction.
➢ Such alternating compression and rarefaction of the surrounding air produces sound
waves which propagate in the form of sinusoidal path.
ADVERSE EFFECT OF NOISE
➢ Noise found to interfere with activities at three levels;
a) audio logical level in referring with the satisfactory performance of
the hearing mechanism
b) biological level interfering with the biological functioning of the
body
c) behavioural level affecting the sociological behaviour of the subjects.
➢ Noxious has been known as to cause of nervous disorder, headache, high blood
pressure and short memory.
➢ the various psychological effects of noise are follows:
A. Depression and fatigue reduces the efficiency of person.
B. Insomnia as a result of lack of undisturbed and refreshing sleep.
C. Straining of senses and annoyance as a result of slow but persistent noise
from motorcycles, alarm clocks, call bells, telephone rings etc.
D. Affecting of psychomotor performance of a person by a sudden loud noise.
E. It is a cause of frustration and is associated with difficulty in concentration,
disturbance of rest, physical and mental fatigue.
➢ Various physiological and pathological effects of nois e pollution are:
a) Noise pollution affects human health, comfort and efficiency.
b) It cause contraction of blood vessels, the skin pale, leads to excessive secretion
of adrenalin hormone into blood stream which is responsible for high blood
pressure.
c) It cause muscles to contract leading to nervous breakdown, tension and even
insanity.
d) Noise effects are axiently, stress reaction and fright.
e) These adverse reactions are coupled with a change in hormone content of
blood, which can turn produce increase the rate of heartbeat, constriction of
blood vessels and dilation of pupil of eye.
f) The most acute effect of noise is the impairment of hearing.
g) It diminishes by the damage of some part of auditory system.
h) When exposed to very loud and sudden noise acute damage occurs to the
eardrum.
➢ Sound consists of wave motion in an elastic medium and caused by the vibrations of
molecules.
➢ It is the periodical mechanical disturbance in fluids and solids.
➢ Noise radiates from vibrating surfaces and from vibrating gases.
➢ Sound is produced in environment by alternating pressure changes in the air and is
caused by the vibrations of solid objects or separation of fluids over around or
through holes in solid objects.
➢ These vibrations cause surrounding air to undergo compression then rarefaction.
➢ Such alternating compression and rarefaction of the surrounding air produces sound
waves which propagate in the form of sinusoidal path.
ADVERSE EFFECT OF NOISE
➢ Noise found to interfere with activities at three levels;
a) audio logical level in referring with the satisfactory performance of
the hearing mechanism
b) biological level interfering with the biological functioning of the
body
c) behavioural level affecting the sociological behaviour of the subjects.
➢ Noxious has been known as to cause of nervous disorder, headache, high blood
pressure and short memory.
➢ the various psychological effects of noise are follows:
A. Depression and fatigue reduces the efficiency of person.
B. Insomnia as a result of lack of undisturbed and refreshing sleep.
C. Straining of senses and annoyance as a result of slow but persistent noise
from motorcycles, alarm clocks, call bells, telephone rings etc.
D. Affecting of psychomotor performance of a person by a sudden loud noise.
E. It is a cause of frustration and is associated with difficulty in concentration,
disturbance of rest, physical and mental fatigue.
➢ Various physiological and pathological effects of nois e pollution are:
a) Noise pollution affects human health, comfort and efficiency.
b) It cause contraction of blood vessels, the skin pale, leads to excessive secretion
of adrenalin hormone into blood stream which is responsible for high blood
pressure.
c) It cause muscles to contract leading to nervous breakdown, tension and even
insanity.
d) Noise effects are axiently, stress reaction and fright.
e) These adverse reactions are coupled with a change in hormone content of
blood, which can turn produce increase the rate of heartbeat, constriction of
blood vessels and dilation of pupil of eye.
f) The most acute effect of noise is the impairment of hearing.
g) It diminishes by the damage of some part of auditory system.
h) When exposed to very loud and sudden noise acute damage occurs to the
eardrum.
