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Environmental Health
Lecture -


            Noise & Radiation
8




             EFFECTS ON
            HEALTH
                    Dr.Shahid Mahmood
                                 Assistant Professor
                        Department of Community Medicine
                                              FJMC Lahore
Acknowledgement
 Park K. Textbook of Preventive and
  Social Medicine
 Maxcy- Rosenau-Last. Public health
  and Preventive Medicine
o World Health Organization (WHO)
 Iliyas-Shah-Ansari . Public health
  and Community Medicine
 www.google.com/images
Learning Objectives
At the end of this session, Students will
be able to :

1.   Define Noise and sources of Noise in
     our surroundings.
2.   Describe the sources of radiation, its
     types and associated health hazards.
3.   Explain the methods to prevent and
     control the unhealthy effect from Noise
     and Radiation
Sound is the sequence of pressure waves produced
by oscillations, propagated through Medium (Solids,
gas, liquids)




                                         Wavelength
20th Century = CENTURY OF NOISE   Noise ‘Definition’         Stress factor



                                  Wrong Sound

                                    In   Wrong Place

                                    At   Wrong Time


                                                       Unwanted Sound??
                                                          Subjective ??
Noise – Properties
    Loudness / Intensity                  Frequency
 Depends on Amplitude of         Frequency is no. of
vibrations                       waves passing a point
                                 per unit time
 Measured in decibels
                                    Higher f= High sound
(dB)

  50 dB means that sound Measured in Hertz(Hz)
is 50 times more intense            1 Hz = 1 wave per
than lowest                        second
distinguishable (reference) Human ear can hear:
sound                                 20 Hz – 20,000 Hz
                                      < 20 = Infra –audible
Upper tolerable limit isterm joining 20,000 and frequency =
Noise expressed in Psycho-acoustic
                                      > loudness = ultrasonic
Sources of Noise in
 Environment
   Automobile (Pressure Horns)

 Factories (Machines/ Vibrating
tools)

 Air crafts & trains

 Musical instruments

 Human voices (class room…?)

 Mega Phones use , Mobile
tones

 TV , radio , Loud speakers
Noisy spots (Noise Polluted
areas)
     Bus terminals
     Traffic congested
      area
      Air ports
     Railway lines
     Area of festivity
     Music shows
Measuring Sound / Noise levels
Sound level meter measure the sound/noise on a
weighted curve called Curve A - Expressed as dB [A]




                                          Sound level meters
Octave band Analyzer with computer program

                                       High
    Low                                pitch
    pitch




    Audiometer and its tracing
Usual Sound levels at various
places
Acceptable Noise level
(Standard)
     Area         Spot      Sound Level (dBA)
                                   25
Residential   Bed room
              Living room          40
                                  35-45
Commercial    Office
              Conference          40-45
              Restaurant          40-60
                                  40-60
Industrial    Workshop
              Laboratory          40-50
                                  35-40
Educational   Class room
              Library             30-40
                                  20-35
Hospitals     Wards
Noise Pollution
Auditory                   Effect
Auditory fatigue – 90 dB ; 4000 Hz (buzzing &
whistling in ears )
Deafness (hearing loss)
Temporary [ Sudden exposure; 24 hours; 4000-6000Hz ]
Permanent [ Chronic exposure >100dB; affect
internal ear, organ of corti; rupture of tympanic
membrane (160dB); usually Occupational;

 Non-Auditory
 1. Speech disturbance (traffic, stations) – SIL 12dB
 2. Annoyance : Irritation , Short temperedness, impatience
 3. Reduction in work efficiency – economic loss
 4. Physiological changes : Sleeplessness, increase pulse,
 BP, Breathing , sweating , nausea,
Principles of Noise Control
Sound abatement methods
(reducing sound generation and
transmission)
1. Sound Insulation : reducing
   transmission by introducing barrier
   – Thick glass , concrete material
2. Sound Absorption – tiles , forms
  and fiber-glass
3. Vibration dumping - Application of
  material of surface- wooden plateform
Noisy spots (Noise Polluted
areas)
     Bus terminals
     Traffic congested
      area
      Air ports
     Railway lines
     Area of festivity
     Music shows
Prevention and Control
(Noise pollution)

1. Proper Town Planning :
 Separate industrial, residential and traffic zones
 Wide green belts between main roads and
 residences
 Wide roads to accommodate traffic
2. Control of vehicles and
  Pressure horns
 Heavy vehicles – Not
   allowed on narrow
   street –traffic jam
 Pressure horns
   prohibited , drivers
   educated
3. Using insulation
   material in buildings
4. Reducing sound
   generation at various
   industrial activity
   spots
Noise control Measures
3.   Periodic monitoring- sound
     levels both in industrial and
     residential areas for
     surveillance
4.   Periodic examination of
     workers in noisy working
     conditions , rotating their jobs,
     proving them protective
     gadgets
5.   Health education (community)
Radiation is a process in which energetic particles
or energetic waves travel through a medium or
Radiation types

  Ionizing     • Electromagnetic radiations
 radiation     • X-rays (15-20cm) ; gamma rays
 (ability to     (50cm)
 penetrate     • Corpuscular radiations
 tissues &     • Alpha particles (0.05mm) –   more
 deposit its    harmful
  energy )     • Beta Particles (0.06-4mm)
               • Proton




                                                     Electromagnetic
Non-Ionizing        Ultraviolet radiations (UV)
  radiation         Visible light
   ( longer        Infrared radiation
wavelength and      microwave radiation
 low energy)        radio-frequency radiation
Measuring radiation
      Radioactivity Unit
      No. of nuclear disintegration per unit time
      of radioactive material

     Unit of radioactive activity = Becquerel
     (Bq)
     1 Bq = 1 disintegration per second
     Radiation Potency (strength of radiation)
     1. Roentgen – unit of exposure
     2. Rad – Unit of absorbed dose
     3. Rem – Unit measuring Potential to health
        A new International system(SI) of unit have now
        replaced Roentgen= Coulomb ; Rad = Gray ;
        Rem = Sievert
Dose equivalent (Sievert ) ‘ Sv’ = D (absorbed dose- Gy) x Q (quality factor)
                         [ Value of Q factor for X-rays = 1 & Particles = 20 ]
Natural background radiation
Sources of Radiation
         exposure
      Natural                       Man- Made
      Sources
Cosmic rays                   Medical & dental
                              X-rays , Radio-isotopes

Environmental                 Occupational Exposure
Atmospheric                   (Radium / uranium )
Terrestrial
Internal                      Nuclear accidents
Potssium -40                  (Chernobyl)
Carbon-14                     Exposure for many years

Total natural radiation per   TV , computer, Mobile,
year exposure = 0.1           Luminous markers,
                              radioactive dial watches
Biological Effects of ionizing
            radiation
                                                       Radiation
                                                       sickness
                                         Immediate
                                                     Acute radiation
                                                       syndrome
                       Somatic
                       ( Affect the                    Leukemia
                        individual
                        exposed)
                                                     Carcinogenesis

Biological effects                        Delayed
                                                        Fetal
                                                     development
                                                     abnormalities
                      Genetic
                                      Chromosomes    Shortening of
                     ( Affect next      mutations         life
                     generation)
E Radiation Protection- Radiation
d Hygiene
u 1. Natural radiation of 0.1 rad pose no hazard
c 2. Permissible dose for man-made is 5 rad per
a X-ray department hygiene
     year.
t
   1. Unnecessary x-rays should be avoided (one
i
      short = 4 rad), especially children /pregnant
o
      women
n
   2. Proper surveillance of X-rays plant ,
      measurement of radiation in that area and
      surrounding
   3. Protection of workers using lead shield,
      apron
   4. Workers should wear film badge or
      dosimeter showing accumulated exposure
International agencies working for
Radiation Protection
 International Commission on
 Radiological Protection (ICRP)
 International Atomic energy
 Agency(IAEA)
 World health Organization (WHO )
Peaceful use of Atomic energy
Develop standards and code of
practice
Periodic inspection of nuclear sites
Agreement on reducing nuclear
weapons
Noise &amp;  Radiation  health Effect

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Noise &amp; Radiation health Effect

  • 1. Environmental Health Lecture - Noise & Radiation 8 EFFECTS ON HEALTH Dr.Shahid Mahmood Assistant Professor Department of Community Medicine FJMC Lahore
  • 2. Acknowledgement  Park K. Textbook of Preventive and Social Medicine  Maxcy- Rosenau-Last. Public health and Preventive Medicine o World Health Organization (WHO)  Iliyas-Shah-Ansari . Public health and Community Medicine  www.google.com/images
  • 3. Learning Objectives At the end of this session, Students will be able to : 1. Define Noise and sources of Noise in our surroundings. 2. Describe the sources of radiation, its types and associated health hazards. 3. Explain the methods to prevent and control the unhealthy effect from Noise and Radiation
  • 4. Sound is the sequence of pressure waves produced by oscillations, propagated through Medium (Solids, gas, liquids) Wavelength
  • 5. 20th Century = CENTURY OF NOISE Noise ‘Definition’ Stress factor Wrong Sound In Wrong Place At Wrong Time Unwanted Sound?? Subjective ??
  • 6. Noise – Properties Loudness / Intensity Frequency  Depends on Amplitude of  Frequency is no. of vibrations waves passing a point per unit time  Measured in decibels Higher f= High sound (dB)  50 dB means that sound Measured in Hertz(Hz) is 50 times more intense 1 Hz = 1 wave per than lowest second distinguishable (reference) Human ear can hear: sound 20 Hz – 20,000 Hz < 20 = Infra –audible Upper tolerable limit isterm joining 20,000 and frequency = Noise expressed in Psycho-acoustic > loudness = ultrasonic
  • 7. Sources of Noise in Environment  Automobile (Pressure Horns)  Factories (Machines/ Vibrating tools)  Air crafts & trains  Musical instruments  Human voices (class room…?)  Mega Phones use , Mobile tones  TV , radio , Loud speakers
  • 8. Noisy spots (Noise Polluted areas)  Bus terminals  Traffic congested area  Air ports  Railway lines  Area of festivity  Music shows
  • 9. Measuring Sound / Noise levels Sound level meter measure the sound/noise on a weighted curve called Curve A - Expressed as dB [A] Sound level meters
  • 10. Octave band Analyzer with computer program High Low pitch pitch Audiometer and its tracing
  • 11. Usual Sound levels at various places
  • 12. Acceptable Noise level (Standard) Area Spot Sound Level (dBA) 25 Residential Bed room Living room 40 35-45 Commercial Office Conference 40-45 Restaurant 40-60 40-60 Industrial Workshop Laboratory 40-50 35-40 Educational Class room Library 30-40 20-35 Hospitals Wards
  • 13. Noise Pollution Auditory Effect Auditory fatigue – 90 dB ; 4000 Hz (buzzing & whistling in ears ) Deafness (hearing loss) Temporary [ Sudden exposure; 24 hours; 4000-6000Hz ] Permanent [ Chronic exposure >100dB; affect internal ear, organ of corti; rupture of tympanic membrane (160dB); usually Occupational; Non-Auditory 1. Speech disturbance (traffic, stations) – SIL 12dB 2. Annoyance : Irritation , Short temperedness, impatience 3. Reduction in work efficiency – economic loss 4. Physiological changes : Sleeplessness, increase pulse, BP, Breathing , sweating , nausea,
  • 14. Principles of Noise Control Sound abatement methods (reducing sound generation and transmission) 1. Sound Insulation : reducing transmission by introducing barrier – Thick glass , concrete material 2. Sound Absorption – tiles , forms and fiber-glass 3. Vibration dumping - Application of material of surface- wooden plateform
  • 15. Noisy spots (Noise Polluted areas)  Bus terminals  Traffic congested area  Air ports  Railway lines  Area of festivity  Music shows
  • 16. Prevention and Control (Noise pollution) 1. Proper Town Planning :  Separate industrial, residential and traffic zones  Wide green belts between main roads and residences  Wide roads to accommodate traffic
  • 17. 2. Control of vehicles and Pressure horns  Heavy vehicles – Not allowed on narrow street –traffic jam  Pressure horns prohibited , drivers educated 3. Using insulation material in buildings 4. Reducing sound generation at various industrial activity spots
  • 18. Noise control Measures 3. Periodic monitoring- sound levels both in industrial and residential areas for surveillance 4. Periodic examination of workers in noisy working conditions , rotating their jobs, proving them protective gadgets 5. Health education (community)
  • 19. Radiation is a process in which energetic particles or energetic waves travel through a medium or
  • 20. Radiation types Ionizing • Electromagnetic radiations radiation • X-rays (15-20cm) ; gamma rays (ability to (50cm) penetrate • Corpuscular radiations tissues & • Alpha particles (0.05mm) – more deposit its harmful energy ) • Beta Particles (0.06-4mm) • Proton Electromagnetic Non-Ionizing  Ultraviolet radiations (UV) radiation  Visible light ( longer Infrared radiation wavelength and  microwave radiation low energy)  radio-frequency radiation
  • 21. Measuring radiation Radioactivity Unit No. of nuclear disintegration per unit time of radioactive material Unit of radioactive activity = Becquerel (Bq) 1 Bq = 1 disintegration per second Radiation Potency (strength of radiation) 1. Roentgen – unit of exposure 2. Rad – Unit of absorbed dose 3. Rem – Unit measuring Potential to health A new International system(SI) of unit have now replaced Roentgen= Coulomb ; Rad = Gray ; Rem = Sievert Dose equivalent (Sievert ) ‘ Sv’ = D (absorbed dose- Gy) x Q (quality factor) [ Value of Q factor for X-rays = 1 & Particles = 20 ]
  • 23. Sources of Radiation exposure Natural Man- Made Sources Cosmic rays Medical & dental X-rays , Radio-isotopes Environmental Occupational Exposure Atmospheric (Radium / uranium ) Terrestrial Internal Nuclear accidents Potssium -40 (Chernobyl) Carbon-14 Exposure for many years Total natural radiation per TV , computer, Mobile, year exposure = 0.1 Luminous markers, radioactive dial watches
  • 24. Biological Effects of ionizing radiation Radiation sickness Immediate Acute radiation syndrome Somatic ( Affect the Leukemia individual exposed) Carcinogenesis Biological effects Delayed Fetal development abnormalities Genetic Chromosomes Shortening of ( Affect next mutations life generation)
  • 25. E Radiation Protection- Radiation d Hygiene u 1. Natural radiation of 0.1 rad pose no hazard c 2. Permissible dose for man-made is 5 rad per a X-ray department hygiene year. t 1. Unnecessary x-rays should be avoided (one i short = 4 rad), especially children /pregnant o women n 2. Proper surveillance of X-rays plant , measurement of radiation in that area and surrounding 3. Protection of workers using lead shield, apron 4. Workers should wear film badge or dosimeter showing accumulated exposure
  • 26. International agencies working for Radiation Protection  International Commission on Radiological Protection (ICRP)  International Atomic energy Agency(IAEA)  World health Organization (WHO ) Peaceful use of Atomic energy Develop standards and code of practice Periodic inspection of nuclear sites Agreement on reducing nuclear weapons

Hinweis der Redaktion

  1. made up of changes in air pressure in the form of waves. Frequency is the property of sound that most determines pitch.[3] The frequencies an ear can hear are limited to a specific range of frequencies.Mechanical vibrations perceived as sound travel through all forms of matter: gases, liquids, solids, and plasmas. The matter that supports the sound is called the medium. Sound cannot travel through a vacuum.The audible frequency range for humans is typically given as being between about 20 Hz and 20,000 Hz (20 kHz). High frequencies often become more difficult to hear with age. Other species have different hearing ranges. For example, some dog breeds can perceive vibrations up to 60,000 HzA sound wave is a periodic variation in air pressure.Distance between two consecutive crests or troughs.Pitch is an auditoryperceptual property that allows the ordering of sounds on a frequency-related scale.
  2. Sound, like all waves, has properties which allow us to tell the difference between seperate sound waves.Vibrations Vibrations is where sound is created it is the source of all sound. When vibrating objects push together they create little zones of compressed air. When the zones of compressed air are released they spring out causing zones of compression and refraction that travel outward from the source. Which creates sound waves.Wavength  Amplitude Amplitude is the maximum distance a particle moves from its resting position. Amplitude is also the height of a sound wave. A quiet sound has a lower amplitude and a loud sound has a higher amplitude.   Speed  Volume  Resonance
  3. X-ray and gamma rays are short wavelength , but deep penetrating so used for diagnostic and therapeutics. Alpha particles are more dangerous when substance inhaled or through wound. X-rays are man made whereas gamma are emitted from radioactive substances. There is no difference between these two .cosmic rays also contains ionizing radiation.
  4. Number of ions produced in 1 ml of air is roentgen. Amount of radioactive energeyabsored per gram of tissue . Rem is the absorbed dose and modifying factor.
  5. Natural background radiation arises from three sources: cosmic radiation from outer space, weaken as enter our atmosphere. Terrestrial radiation comes from radioactive material such as uranium , thorium, in soil, rocks, . Atmospheric radiation from gases like radon, thoron. Internal radiation in man from small amount of radioactive material stored in body like uranium, thorium and isotopes of potassium, strontium 90, K 40, Most important exposure is the man made. People exposed to the x-rays are the pateinets, medical (0.02-3 rad per years). Half life of sr90 is 28 years .
  6. Dose of 400-500 reoentgen is fatal for 50% exposed. 25 gives rise to lassitude, WBC breakdown. Acute effect range ofrom nausea , vomiting and bleeding
  7. .