Particulate, Gas

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Particulate, Gas Vapor(Sampling Equipment)

• Cindy Hammons

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PARTICULATE
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Definitions

• Aerosols the dispersion of solid or liquid
  particles in the gaseous medium
• Dust dispersion of solid particles in the
  gaseous medium
• Fumes solid particles in a gaseous medium
  formed by condensation of solid materials (vapor)
• Smoke usually but not necessarily consist of
  solid particles

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Shape, Size and Distribution

• Various shape, size and density of particulate
• AED is the diameter of a unit density sphere
  having the same settling velocity as the particle
  concern
• Polydisperse dust cloud (geometric mean and
  geometric standard deviation)

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Aerodynamic Behavior In Airstream

• Impaction proportional to the momentum i.e.
  mass and velocity
• Sedimentation proportional to its diameter
• Diffusion for particles lt 0.1um

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Size Selective and Selected Area of Deposition

• Nasopharyngeal deposition (upper respiratory
  tract) 7 to 20um
• Tracheobronchial (conducting airways) 5 to 7um
• Alveolar region (gas exchange area) 0.5 5um

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Inhaled Dust Fractions (Sampling Instrument)

• Respirable dust the dust fraction that will
  penetrate to the unciliated portion of the lungs

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Purpose of Sampling

• Compliance with the requirement of the law
• Health risk assessment
• Epidemiological study
• Assessment of control measures

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Type of Sampling

• Area sampling
• Personal sampling

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Type of Sample Equipment

• Total dust
• Inspirable dust 7 hole sampler, IOM sampler,
  close face sampler
• Respirable dust BMRC horizontal elutriator, AEC
  cyclone
• Thoracic dust vertical elutriator
• Fibers open face sampler with cowl

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Sampling Equipment

• Real time piezobalance, dust counter etc
• Non real time filtration, impaction (cascade
  impactor)

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GAS VAPOR
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Definitions

• Gas a state of matter in which a substance
  completely fills the region in which it is
  contained has very low density and viscosity
  can expand and contract greatly in response to
  changes in temperature and pressure and easily
  diffuses into other gases e.g., CO, CO2, HCN,
  NH4, SO2, H2S, N2O, O3, Formaldehyde, phosgene,
  arsine, vinyl chloride etc

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• Vapour the gaseous state or form of a substance
  which is normally in the liquid or solid state at
  room temperature and pressure. The liquid or
  solid may be reduced to the vapor by the action
  of heat. A vapor can be liquefied by a suitable
  increase in pressure e.g., toluene, xylene,
  alcohol, C2S, benzene, carbon tetrachloride etc

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Physiological Effects

• Carcinogens vinyl chloride, benzene, benzidine,
  B-napthylamine, formaldehyde
• Systemic poisons C2S, parathion, hexane,
  chlorinated hydrocarbon
• Asphyxiation CO, CH4, HS, Na Nitrite
• Irritation acid, alkali, O3, N2O, phosgene
• Anesthetic/narcosis alcohol, ketones
• Sensitizer TDI, formaldehyde

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Physicochemical Properties

• Solubility
• Melting and boiling points
• Vapor pressure
• Vapor density or relative density
• Flash point

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CSDS

• Physicochemical properties

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Purpose of Sampling

• Compliance with the requirement of the law
• Health risk assessment
• Epidemiological study
• Assessment of control measures

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Type of Sampling

• Area sampling
• Personal sampling

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Sampling Equipment

• Real time
• Non real time

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Sampling Equipment (examples)

• Charcoal tubes with pump
• Passive sampler (diffusion membrane)
• Bubbler (midget impinger)
• MIRAN
• Portable gas chromatography
• Detector tubes

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Thank You