Metabolic Heat Persons

Reference data and engineering information about metabolic heat persons for thermodynamics applications.

metabolicheatpersons

Overview

Engineering reference data for Metabolic Heat Persons in thermodynamics.

Key Formulas

First Law

$\Delta U = Q - W$

Energy is conserved — heat added minus work done.

Ideal Gas Law

$PV = nRT$

Relates pressure, volume, and temperature of an ideal gas.

Carnot Efficiency

$\eta = 1 - T_C/T_H$

Maximum efficiency between two temperatures.

Variables

Symbol	Description	Unit
$U$	Internal energy	J
$Q$	Heat	J
$W$	Work	J
$P$	Pressure	Pa
$V$	Volume	m³
$T$	Temperature	K

Sensible and latent heat gain from persons at various activity levels and room dry-bulb temperatures (1 W = 3.41 Btu/hr).
Degree of Activity	Typical Application	Metabolic Rate(W)	At 28°C(W)	At 27°C(W)	At 26°C(W)	At 24°C(W)	At 22°C(W)	At 20°C(W)
Seated at rest	Cinema, theater, school	100	5050	5545	6040	6733	7228	7921
Seated, very light work	Computer working	120	5070	5565	6060	7050	7842	8436
Office work	Hotel reception, cashier	130	5080	5674	6070	7060	7852	8644
Standing, walking slowly	Laboratory work	130	5080	5674	6070	7060	7852	8644
Walking, seated		150	5397	5892	6486	7674	8466	9060
Moderate work	Servant, hair dresser	160	55105	60100	6892	8080	9070	9862
Light bench work	Mechanical production	220	55165	62158	70150	85135	100120	115105
Moderate	Dancing Party	250	62188	70180	78172	94156	110140	125125
Fast walking	Mountain walking	300	80220	88212	96204	110190	130170	145155
Heavy work	Athletics	430	132298	138292	144286	154276	170260	188242

Definitions

Sensible Heat ( $Q_s$ ): The portion of metabolic heat transfer that causes a change in air temperature without a change in phase. It is transferred via convection and radiation.
Latent Heat ( $Q_l$ ): The portion of metabolic heat transfer associated with moisture (sweat) evaporation from the skin. It causes a change in the moisture content (humidity) of the air.

The provided data is based on older ISO and ASHRAE standards. For accurate and current design calculations, always consult the latest editions of these standards (e.g., ASHRAE Handbook - Fundamentals).

References

Original Source

Source: engineeringtoolbox.com