5·8 m3 human heat-sink calorimeter with online data acquisition, processing and control

The construction and performance of a 5·8 m3 heat-sink calorimeter for human use is described. It differs from previously published human calorimeters mainly in the use of a digital computer for realtime measurement and closed-loop temperature control. In addition the computational abilities provide a completely automated system. The performance characteristics of the calorimeter are: (i) a linear response between 0 and 280W for both sensible and evaporative heat, (ii) a 24h stability of less than ±1W (s.d.); (iii) a precision for sensible and evaporative heat better than 1·5 and 2%, respectively, and (iv) time constants (95%) of 14 and 7·5 min for sensible and evaporative heat, respectively.