Thermal Comfort

Also found in: Wikipedia.

Thermal comfort

The appropriate combination of temperatures, warm or cool, combined with air flow and humidity, that allows one to be comfortable within the confines of a building. This comfort is not usually achieved by the fixed setting of thermostats but through careful design and planning.
Illustrated Dictionary of Architecture Copyright © 2012, 2002, 1998 by The McGraw-Hill Companies, Inc. All rights reserved
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Thermal Comfort


a functional condition of the human body characterized by a certain content and distribution of heat in the superficial and deep tissues, with minimum exertion of the heat-regulation mechanism. Such a condition is subjectively regarded as the most preferable.

Objectively, thermal comfort is characterized by a constant body temperature, minimum activity of the sweat glands (imperceptible perspiration at a rate of 40–60 g/hr), and small periodic fluctuations of temperature in the extremities, especially the hands and feet (in the 30°–31°C range). The skin temperature in the trunk region remains almost unchanged at about 33°C, the overall skin temperature is comparatively constant at 32°–33°C, and the cardiovascular, respiratory, digestive, excretory, and other physiological systems function at optimum levels. In addition, thermal comfort is characterized by the highest level of mental readiness. Man experiences thermal comfort in a state of muscular rest with heat production of about 80 kilocalories (kcal) per hr (1 kcal = 4.19 kilojoules) or doing light work, with heat production of no more than 150 kcal/hr (such as the duties of a clerk, engineer, operator, or researcher) and a certain combination of microclimatic parameters—temperature, relative humidity, and rate of air movement and heat emission.

Standards for the microclimate in residential and public buildings to ensure thermal comfort are established in differing ways to take into account various climatic zones, seasons, and age groups. In most healthy adults living permanently in a temperate zone and wearing ordinary indoor clothing, thermal comfort is achieved at an ambient temperature of 18°–22°C in winter and 23°–25°C in summer, with a difference of not more than 3°C between the ambient temperature and the temperature of enclosed areas, with relative humidity of 30–60 percent, and with a rate of air movement of 0.05–0.15 m/sec in winter and 0.2–0.4 m/sec in summer. For an unclothed person the comfort zone is at an ambient temperature of 28°–30°C. The zone of thermal comfort changes somewhat under the influence of such factors as physical exertion, adaptation to heat or cold, and some pathological conditions. It can be broadened by conditioning and hardening the body by taking progressively colder air and water baths, as well as through dynamic microclimatic actions that extend the lower comfort limit. Such steps increase the body’s resistance to colds. At night, lowering of the air temperature by 1°–2°C, together with good heat insulation of the body, is recommended as being conducive to deep sleep. In children during the first years of life (especially in neonates) and in the elderly, the microclimatic comfort zone is narrow because of the functional insufficiency of the heat-regulation mechanisms.

Individual differences in the boundaries of the thermal comfort zone depend on basal metabolism, adaptation, development of subcutaneous fat, and the habit of wearing clothing that provides more or less heat insulation.


Slonim, A. D., and N. M. Voronin. “Vliianie na organizm klimata kak sredstva profilaktiki i kurortnogo lecheniia.” In Osnovy kurortologii, part 1. Moscow, 1959. Pages 20–59.
Goromosov, M. S. Mikroklimat zhilishch i ego gigienicheskoe normirovanie. Moscow, 1963.
Rukovodstvo po kommunal’noi gigiene, vol. 3. Moscow, 1963. Pages 203–51.
Kandror, I. S., D. M. Demina, and E. M. Ratner. Fiziologicheskie prinlsipy sanitarno-klimaticheskogo raionirovaniia territorii SSSR. Moscow, 1974.


The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
In heating ventilation systems, good thermal comfort is described by low-temperature gradient (<1.8[degrees]F/m [1[degrees]C/m]) and low deviation ([+ or -]1.8[degrees]F [1[degrees]C]) from the room setpoint temperature.
The American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE) has announced the publication of the 2017 edition of its major thermal comfort standard.
When subjected to temperature below the thermal comfort zone, the chicks destine part of the ingested energy to generate heat and with this they maintain body temperature, however, with negative reflexes on the productive indices (Yardimci, Sengor, Sahin, Bayram, & Cetingiil, 2006), mainly on feed conversion.
HVAC systems testing and check: a simplified model to predict thermal comfort conditions in moderate environments, Applied Energy 104: 117-127.
According to the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) standards, thermal comfort is defined as, "That condition of mind which expresses satisfaction with the thermal environment." Traditional approaches to design for automotive thermal comfort are inadequate as the metrics focus on the vehicle, seat, and climate components rather than considering the state of the occupant.
[13] used the velocity coefficient as the thermal comfort indicator and discussed the influence of CFD-ANN coupling on the interior design; the computation time was reduced considerably.
Arco recommends a layering system as the best way to dress for optimal warmth and insulation, because it allows the wearer to add or remove pieces to maintain their own thermal comfort. New insulated and waterproof garments from the Winter Weatherwear range have been specifically designed to be worn together.
Achieving thermal comfort for all is usually an elusive endeavor; as a matter of fact, studies cite the lack of thermal comfort as a top workplace complaint.
Thermal comfort and indoor air quality are important factors for energy efficient buildings design [1].
In a paper entitled "Evolving Opportunities for Providing Thermal Comfort," the researchers describe the futility of trying to design indoor environments to static, uniform conditions with no perceptible air movement.
We examined residual limb skin temperatures and perceived thermal comfort (PTC; 11-point Likert scale) of participants with unilateral transtibial amputation (n = 8) who were snowshoeing in a cold environment.
This article presents the findings of the correlation between data of the architectural space volume and the level of thermal comfort of workers who use offices to perform their tasks.