HomeCalculatorsHVAC - Dew Point Approximation

HVAC - Dew Point Approximation

Dew point of moist air from ambient temperature and relative humidity using Magnus formula - the basis for condensation check.

Dew pointHVACPsychrometrics
Dew-point temperature
19.1°C
Formula, assumptions, and limits

Magnus coefficients a = 17.625, b = 243.04 °C. If cargo-tank plating temperature falls below dew point → condensation risk. Cargoes with critical moisture (steel coils, paper) need dry-cargo dehumidification.

Symbol legend

SymbolMeaningUnitSource
Relative humidity%hygrometer
Air temperature°Cthermometer