Title: Indoor Air Quality IAQ and Its Impact upon Building Occupants
1Indoor Air Quality (IAQ) and Its Impact upon
Building Occupants
Center for Occupational Environmental Health at
Hunter College
2Overview
- Which Factors Affect Indoor Air Quality?
- How Does One Approach IAQ Problems?
- Recognize
- Evaluate
- Control
3Definition of IAQ Investigator
- Scientist, Detective, Public Relations, etc.
Health Safety Professional
4Sick Building Syndrome (SBS)
- Acute health and comfort effects linked to the
time spent in workplace, but no specific illness
or cause can be identified - (Upper respiratory complaints, irritation,
fatigue)
5Building-related Illness (BRI)
- Symptoms of diagnosable illness are identified
and attributed to environmental agents in
workplace - (Legionnaires disease hypersensitivity
pneumonitis)
6Factors that Affect Building IAQ
- Sources of Contamination
- The Heating Ventilation, Air Conditioning (HVAC)
System - Pollutant Pathways
- Building Occupants
7Sources of Contamination
- Sources Outside Building (nearby factory)
- Equipment (photocopier)
- Human Activities (micro-waving popcorn)
- Building Components and Furnishings (carpets)
- Other Sources
8Equipment
- HVAC System (heating, ventilation, air
conditioning system) - Office Equipment Supplies (photocopier)
- Other Sources
9Human Activities
- Personal Activities (smoking)
- Housekeeping Activities (mopping with strong
cleaners) - Maintenance Activities (painting)
10Building Components and Furnishings
- Locations that Produce or Collect Dust, Fibers,
or Odors (bathrooms) - Unsanitary Conditions/Water Damage (faucet drip)
- Chemicals Released from Building Components or
Furnishings (roof tarring)
11Other Sources
- Accidental Events (substance spills)
- Special Use Areas/Mixed Use Buildings (pantry)
- Redecorating, Remodeling, Repair Activities
(plumbing)
12The HVAC System (air circulation)
13The HVAC System
- Thermal Comfort (heating and cooling air)
- Ventilation (circulating fresh air)
- Odor and Contaminant Control (filtering air
devices)
14Pollutant Pathways
- Stack Effect - Pressure by Convection
- Air rises when heated and falls when cooled
- Wind Effect - High to Low Pressure
- Air moves from high to low concentrations
15Building Occupants
- Hypersensitive or Susceptible Individuals (people
who get sick easily)
16IAQ Investigations Measurements
- Only when you know what you are looking for do
the measurements become significant
17Recognizing Building IAQ Problems
- Key Questions for IAQ Investigation
- Looking for IAQ Problem Identifiers
18Key Questions for IAQ Investigation
- How Was this Building Originally Supposed to
Function? - Is the Building Functioning as Designed?
- What Changes in Building Layout and Use Have
Occurred Since Original Design and Construction? - What Changes May Be Needed to Prevent Future IAQ
Problems?
19Look for IAQ Problem Identifiers
- Odors
- moldy, chemical, exhaust fume
- Signs of Moisture Damage or Accumulation
- damp or wet surfaces, puddling of water
- Staining or Discoloration
- brownish or yellowish ceiling or carpet tiles
- Presence of Hazardous Substances
- chemical containers, spray bottles, etc.
- Dirty or Unsanitary Conditions
- unclean bathroom, dusty storage room, etc.
20Look for IAQ Problem Identifiers
- Visible Fungal/Bacterial Growth
- mold or slime growth
- Unusual Noises from Lights or Machinery
- may be caused by loose or broken parts
- Inadequate Maintenance
- cracked/peeling walls equipment poorly taped
- Signs of Occupant Discomfort
- cough, watery and/or red eyes, headache)
- Overcrowding
- too many desks, chairs, etc. in room
21Look for IAQ Problem Identifiers
- Blocked Airflow/Poorly Located Vents, etc.
- cardboard covering vent books stacked on vent
- Ceiling Plenums
- (space between the ceiling tiles and ceiling)
- Heat Sources
- space heaters, desk fans
- Special Use Areas
- food pantries, kitchens, copy rooms, bathrooms
22Look for IAQ Problem Identifiers
- Carbon Dioxide (CO2) concentration (ppm)
- exhaled air removed from room (stuffiness)
- Temperature (0F or 0C)
- warmth of room (hot or cold)
- Relative Humidity ()
- moisture level in room - dry (5) or damp (95)
- Carbon Monoxide (CO) concentration (ppm)
- generated by faulty burning (stove/heater/car/et
c.) - Air Circulation
- Is air sucked in (negative pressure) or pushed
out (positive pressure) of room when door opened?
ppm parts per million measurement of volume
23Look for IAQ Problem Identifiers
Indoor Air Quality direct-reading instrument
Gives air quality measurements instantaneously
in the field without having air samples sent to a
laboratory for analysis
Sampling wand Computer display screen Function
control board
24Whats Wrong with this Room?
25Evaluating Building IAQ Problems
- Key Questions for Walkthrough
- Conducting Initial Walkthrough
- Collecting Additional Information, Including
Sampling (If Necessary)
26Key Questions for Walkthrough
- Are There Obvious Pollutant Sources? If so, Are
They Adequately Controlled? - Are There Any Deficiencies in the HVAC System
that Serves the Complaint Area? - Are there Pathways and Pressure Differences
Moving Contaminants into Complaint Area(s) from
Outdoors or from Other Parts of Building?
27Initial Walkthrough
- Collect Info on History of Building and
Complaints - Identify Known HVAC Zones and Complaint Areas
- Notify Building Occupants of Upcoming
Investigation - Identify Key People Needed for Access
Information
28Collecting Additional Information
- Occupant Complaints Data (previous surveys,
complaint letters) - HVAC System Data (maintenance schedule, standard
operation) - Pollutant Pathways Data (how does the air
circulate) - Pollutant Sources Data (where is the problem
coming from) - Air Sampling for Contaminants Identifiers
- Building and Room Occupancy (potential crowding
issues) - Identify Complaints Not Caused by Poor Air
Quality (ergonomic issues poor office furniture
or lighting)
29Controlling Building IAQ Problems
- Source Control
- Ventilation
- Air Cleaning
- Exposure Control
30Controlling Building IAQ Problems
- Source Control
- remove contaminant contaminant generator
- Ventilation
- improve and/or increase air flow
- Air Cleaning
- filter out impurities with specialized air
filters - Exposure Control
- pressurize room to control air flow in and out
31Controlling Building IAQ Problems
Chemical fumes in tent are pumped through large
air filtering device and clean air comes out of
stacks
Air duct cleaning
Tent Air filter Stacks
Air scrubbing device
32CONCLUSION
- QUESTIONS DISCUSSION
- _____________________________________
- ANDREW BURGIE, M.S.
- Center for Occupational
- Environmental Health at Hunter College
- (212) 481-7652