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Indoor Air Quality Guide to Acceptable Conditions
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INDOOR AIR QUALITY ACCEPTABLE CONDITIONSTABLE 1.  TYPICAL AND TRIGGER IAQ PARAMETERS
HUMAN MARKERSTRIGGER CONDITIONS **TYPICAL CONDITIONS *CONDITIONS*
Comfort Issues10% or less complaining of any one thermal conditionGreater percentages than these listed 
20% or less complaining of general thermal conditions
Health IssuesInfectious diseases: 100% protectedAny less than listed
Asthma/allergies/MCS: 95-99% satisfied
PHYSICAL MARKERSTYPICAL CONDITIONS*TRIGGER CONDITIONS**
Temperature68 degrees to 76 degrees FarenheitTemperatures outside this range.
Temperature range in a space.1-3 degrees FarenheitMore than 3 degrees Farenheit
Relative Humidity40-60% RH<30% or >60% RH
Building Under positive pressure; air delivered to occupied spacesDifferent conditions than listed
Air movement on peopleAir velocities > 20fpm but x delivered to occupied spacesDifferent conditions than listed (80% satisfaction)
Air velocities <100-200 fpm when warm
Outdoor air delivery20 cfm/person: officesLess than 15-20 15-20 cfm/person
15 cfm/person: classrooms
Total air delivery to space1 cfm/sq. ft; 6 air changes per hour (offices)Different conditions than listed
CHEMICAL MARKERSTYPICAL CONDITIONS*TRIGGER CONDITIONS**
Carbon dioxide400 to 1100 ppm700+bkgrnd (ASHRAE 62-1999)
TVOC300 mg/m3 (    1-2 ppm)(approximately 1-2 ppm)Depends on compound; 300 mg/m 3 to 3000 mg/m 3
Formaldehyde0.005 - 0.05 ppm>0.05 ppm (60 ug/m 3) 60 mg/m 3
Carbon monoxide1 - 3 ppm> 3 ppm
NO20.01 - 0.05 ppm0.05 ppm
Ozone0.01 - 0.02 ppm> 0.02 ppm
Particlesup to 50 mg/m 3 (total)any visible aerosols (e.g., dust smoke); high quantities 
up to 15 mg/m 3 (PM 2.5)of settled dust on flat surfaces; visible particles emitted 
from supply registers
Bioaerosols varies widely with site/locateCounts 2-3X greater than other spaces or outdoors
Asbestos< 0.01 fb/cc> 0.01 fb/cc
< 2  g/m 3
Radon < 0.5 pCi/lit> 4 pCi/lit (EPA recommended standard)
Odors"none"Any detectable for extended periods of time
* Non-industrial environments, e.g., office space, classroom, conference room. **Trigger means "take note,"  "investigate."  
Caution:  Do not use the Table for compliance or design; always obtain competent professional assistance.  Source:  IAQ and HVAC Workbook, 2002, D. Jeff Burton.