The invention provides a forced air warmer comprising: a chamber having an outlet port an air heater arranged to heat air within the chamber an air propagator arranged to propagate heated air from the chamber along a heated air flow path passing through the port and a temperature sensor provided in the heated air flow path to measure the temperature of heated air propagated along the heated air flow path. The forced air warmer further comprises an air flow conditioner in the heated air flow path downstream of the temperature sensor, the air flow conditioner being arranged to condition air flow at the temperature sensor so as to improve the reliability of temperature measurements made by the temperature sensor. The forced air warmer may be used to supply heated air to an air warming blanket for regulating the temperature of a patient.
