MODULE 1

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• MODULE 1

• INPUT DATA REQUIREMENTS

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TYPES OF INPUT DATA

• Source/spill data
• Meteorological data
• Site data
• Receptor data
• Air quality data (background, ambient and indoor)
• Deposition data
• Risk data

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NEED FOR INPUT DATA

• To assure optimum performance of the model
• To find the possible source of emissions and
  rectify it

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SOURCE/SPILL DATA

• Emission rate
• Physical and chemical data
• Geometry and location of source
• Plant operation
• Terrain features near the source
• Fraction of liquid, gas and aerosol

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METEOROLOGICAL DATA

• Typical meteorological data include
• Wind velocity
• Cloud cover and net radiation
• Temperature
• Turbulence
• Relative humidity
• Atmospheric stability

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Meteorological data are collected
by weather bureau pollution control
agencies industries and local universities

• Meteorological stations
• Generally one for flat terrain and more
  than
• one for complex terrain.

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SITE DATA

• A Site map shows
• location of sources
• dimensions of nearby buildings
• terrain features (urban/rural)
• surface roughness
• Other equipment locations
• Plant boundaries
• Site data helps in classifying downwash conditions

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Point or site where air pollution concentration
is measured is called the receptor site

• Common grids used for placing receptor sites are
• Square grid
• Rectangular grid
• Circular grid
• Irregular grid

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SQUARE GRID CIRCULAR GRID
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Location or placing of receptor points

• The receptor points should be located in a manner
  that
• Points of maximum concentration should be spotted
• Sensitive places like schools, day care centers,
  hospitals, old age homes etc. are included
• Highly populated areas and water bodies are
  covered

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BACKGROUND AIR QUALITY DATA

• At any time there is some concentration of
  pollutant which is present in the atmosphere due
  to natural sources as well as unidentified man
  made sources.
• Important factors to be considered for
  background air quality data are
• the point or area where there is a conjunction
  of all the sources
• the point of maximum impact from the source
• the area of maximum impact from other (nearby)
  sources.

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AIR QUALITY DATA

• Background concentration
• Ambient air concentration
• Indoor concentration

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DEPOSITION DATA

• The pollutant after its release into the
  atmosphere gets deposited on
• Water
• Land
• Vegetation
• Snow
• Data required Deposition velocity, Precipitation
  rate
• These deposition data are then used to estimate
  risk through non-inhalation pathways

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The risk data includes the following

• Exposed population
• Exposure routes
• Inhalation route
• Non-inhalation route
• Unit risk factors
• Potency slopes
• Chronic reference dose

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• The chemicals are classified as either
• carcinogenic or
• non-carcinogenic
• Exposures may be
• intermittent
• chronic
• Multi exposure pathways for each chemical should
  be studied

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Primary pathways are those in which the pollutant
enters the human body directly.

• The data are required for the following primary
  pathways
• dermal exposure
• water ingestion
• crop ingestion (direct deposition)
• soil ingestion

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Secondary pathways are those in which the
pollutants are acquired by humans from a source
which is infected by the pollutant already.

• The data are required for the following secondary
  pathways
• Mothers milk
• Fish ingestion
• Crop ingestion (root uptake)
• Poultry meat and eggs
• Meat (others)
• Dairy products

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• The slope factor for a chemical relates the
  chronic dose to the lifetime risk.
• Slope factor risk / unit dose
• For a non-carcinogenic chemical
• Hazard index dose / chronic reference dose