Human Response to One Hour Pollutant Exposure (Turco, p194)
Symptom
Concentration
Parts per million by mass
Pollutant
Death (may be
delayed)
150 ppmm
Acute asthma
25-100
ppmm
Breathing
difficulty
1.5-5.0
ppmm
Respiratory impact (long term
exposure promotes disease)
0.06-0.1
ppmm
NO2