NOISE ENVIRONMENT IMPACT ANALYSIS by Dr. I.D. Mall Department of Chemical Engg.Indian Institute of Technology, RoorkeeRoorkee- 247667

1. NNOOIISSEE EENNVVIIRROONNMMEENNTT IIMMPPAACCTT
AANNAALLYYSSIISS
Dr. I.D. Mall
Department of Chemical Engg.
Indian Institute of Technology, Roorkee
Roorkee- 247667

2. NOISE:
• Unwanted sound or sound in wrong place at wrong time.
• Any sound that is undesirable because it interferes with speech
and hearing, intense enough to damage hearing.
• Noise has adverse impact on human beings and their
environment. Noise can also disturb natural wild life and
ecological systems.
Industrial
Noise
Community Noise

3. • CONSTRUCTIVE NOISE:
Can be significant source of Community
• OPERATIONAL PHASE NOISE:
Noise emission from pump, compressors,
highways, power plants, recovery boilers,
blast furnace areas, military training
activities.

4. • NOISE EMISSIONS:
• Impulse Noise: of short duration of high
density- explosions, sonic booms and
artillery fire.
• Continuous Noise: Longer duration, lower
intensity – from construction traffic

5. NNOOIISSEE IIMMPPAACCTT OONN HHUUMMAANN SSYYSSTTEEMM
• Auditory effect:
– Noise induced hearing
– Communication disturbances
– Acoustic trauma
• Non-auditory effect:
– Psychological disturbances like annoyance,
absenteeism, poor work performance.
– Physiological disturbances like blood pressure,
sleeplessness. Loss of appetite.

6. NNOOIISSEE IIMMPPAACCTT OONN HHUUMMAANN SSYYSSTTEEMM
• Damage hearing or health
• Interference with work tasks
• Interference with speech communication
• Affect inter room privacy
• Interference with sleep
• Cause annoyance
• Ecological effects on wild life
• Effect on domestic and farm animal
• Sleep disturbance

8. RREEDDUUCCTTIIOONN OOFF IINNDDUUSSTTRRIIAALL NNOOIISSEE
Maintenance
• Replacement or adjustment or warn and loose or
unbalanced parts
• Lubrication of machine parts and use of cutting oil
Substitution of machine
• Press for hammers
• Hydraulic for mechanical presses
Substitution of processes
• Compression for impact riveting
• The driving force of vibrating surfaces may be
reduced by minimizing rotational speed, isolating.

9. MMiittiiggaattiioonn MMeeaassuurreess
• Changing the source of noise.
• The path of noise from the source to receiver.
• The receiver of noise
• Timing
• Reduction of no. of vibrating sources.
• Enclosure of source.
• Attenuation of noise by absorption.
• Firing points should be sized with natural barriers
(valleys, rivers at firing points)

10. MMiittiiggaattiioonn MMeeaassuurreess
• Purchasing of mobile equipment should be in
compliance with emission standards.
• Noise attenuation measures should be utilized in a
building design and construction.
• Design features can be used to reduce the noise for
specific sources.
• Noise mitigation may be facilitated by development
of a Comprehensive noise management program.
(Operating paths, flight paths, loading and take-off
controls).
• Use of local noise reflectors.

11. NNOOIISSEE CCOONNTTRROOLL FFOORR RROOAADDSS
• Barrier to obstruct or dissipate
sound emission.
• Elevated or depressed high way.
• Absorption effect of land escaping

12. BBaassiicc IInnffoorrmmaattiioonn oonn NNooiissee
• SPL = 20 log (P/Po)
SPL = sound pressure level dB
P = sound pressure Mbar
Po = reference pressure 0.0002 Mbar (the threshold
of human being)
• Sound Intensity, I = W(sound power)/A
• Sound power level, Lw = 10 log(W/Wo)
Wo = 10-12 reference sound power
W = sound power emitted by the source
• Sound Intensity Level, LI = 10 log (I/Io)
Io=Reference intensity = 10-12 w/m2

13. DDeepplleettiioonn ooff NNooiissee lleevveell dduuee ttoo
GGrreeeenn bbeelltt ddeevveellooppmmeenntt
• The sound pressure level generated by a
noise source decrease with increasing
distance from the source due to work
divergence.
• Lp = Lw – 20 log r – Ae – 8 dB
• Lp2 = Lp1 – 20 log (r2/r1) – Ae(1,2)
– Lp1 = source pressure level at a distance r1
– Lp2 = source pressure level at a distance r2
• Attenuation by vegetation can be:
– Attenuation by air absorption
– Attenuation by vegetation

14. SSTTEEPPSS IINN NNOOIISSEE EENNVVIIRROONNMMEENNTT
IIMMPPAACCTT AANNAALLYYSSIISS
• Step 1: Identification of noise impacts of proposed
Project
• Step 2: Preparation of description of existing noise
Environment conditions
• Step 3: Procurement of relevant noise standards
and/or guide lines
• Step 4: Impact prediction
• Step 5: Assessment of impact significance
• Step 6: Identification and incorporation of mitigation
measures

15. THANK
YOU