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Metabolic Heat Gain from Persons

Human metabolic heat gain in air conditioned rooms.

The table below indicates sensible and latent (vapor) heat from persons. The values can be used to estimate heat loads that must be handled by air conditioning systems.

Note that the values are based on older ISO and ASHRAE standards. Later ISO and ASHRAE standards should be checked for updated values.

For full table - rotate the screen!

Metabolic Heat Gain from Persons
Degree of Activity	Typical Application	Average Metabolic Rate - male adult (W)	Room Dry Bulb Temperature (^oC)
			28		27		26		24		22		20
			Heat (W)
			Sens.	Lat.	Sens.	Lat.	Sens.	Lat.	Sens.	Lat.	Sens.	Lat.	Sens.	Lat.
Seated at rest	Cinema, theater, school	100	50	50	55	45	60	40	67	33	72	28	79	21
Seated, very light work	Computer working	120	50	70	55	65	60	60	70	50	78	42	84	36
Office work	Hotel reception, cashier	130	50	80	56	74	60	70	70	60	78	52	86	44
Standing, walking slowly	Laboratory work	130	50	80	56	74	60	70	70	60	78	52	86	44
Walking, seated		150	53	97	58	92	64	86	76	74	84	66	90	60
Moderate work	Servant, hair dresser	160	55	105	60	100	68	92	80	80	90	70	98	62
Light bench work	Mechanical production	220	55	165	62	158	70	150	85	135	100	120	115	105
Moderate Dancing	Party	250	62	188	70	180	78	172	94	156	110	140	125	125
Fast walking	Mountain walking	300	80	220	88	212	96	204	110	190	130	170	145	155
Heavy work	Athletics	430	132	298	138	292	144	286	154	276	170	260	188	242

1 W = 3.41 Btu/hr

Heat Generated from Human Body

The diagram below is for moderate activity- seated, very light work - computer working person.

Human body heat - metabolism

sensible heat = convection and radiation
latent heat = evaporation

Related Topics

Air Conditioning Systems
Design of Air Conditioning systems - heating, cooling and dehumidification of indoor air for thermal comfort.
Air Psychrometrics
Moist and humid air calculations. Psychrometric charts and Mollier diagrams. Air-condition systems temperatures, absolute and relative humidities and moisture content in air.
Physiology
Human physiology vs. air quality, comfort temperatures, activity and metabolic rates. Health effects of gases adn polutions like carbon monoxide and more.

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