UNIT 3
CONCENTRATION CONVERSION CALCULATION EXAMPLES
HPEO 408 Occupational Health Hazards
ppm ↔ mg/m3 CONVERSIONS
Where:
MW = molecular weight of substance in g/mol
24.45 = molar volume of air in liters at normal temperature and pressure (NTP)
NTP = Temperature (25oC)Pressure (1 atm / 760 mm Hg)
NOTE: if not NTP conditions molar volume may require adjustment
EXAMPLE 1
EXAMPLE 2