Air Pollution MicroScale Indoor Air

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Air Pollution - Micro-Scale (Indoor Air)

• CE 511 - April 28, 2006

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Micro-Scale (Indoor) Air Pollution

• In cold climates, people spend 70 - 90 of their
  time indoors
• Sometimes indoor air more polluted than outdoor
• Sources of indoor air pollution
• Combustion
• CO from malfunctioning furnace, gas stoves, pilot
  lights, smoking
• NOx - Can be quite high
• SO2 - Typically low
• Particulates - cigarette smoke

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Gaseous Combustion Products
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Respirable PM - Smoking
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Micro-Scale (Indoor) Air Pollution

• Bioaerosols - viruses, bacteria
• Radon - why?
• Heavy metals - tracked in from outside
• arsenic, mercury, chrome, lead (lead and mercury
  could be from paint)
• gt 300 VOCs (volatile organic compounds)
• formaldehyde (CH2O) is one of the most prevalent
• CH2O emitted by pressed wood, foam insulation,
  textiles
• CH2O concentration will decrease with ventilation

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Indoor Air Quality Model
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Indoor Air Quality Model - Solutions

• 1. General
• 2. Steady-state

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Example

• Calculate the steady-state CO concentration in a
  poorly ventilated room (V 80 m3, Qin Qout
  0.5 ach) in which 4 card players have been
  smoking for several hours, each at a rate of 4
  cigarettes per hour. Assume each cigarette
  produces 125 mg CO and that CO decays with a rate
  constant k 0.1 h-1.

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Respirable PM - Smoking