Room temperature (also referred to as ambient temperature) is a common term to denote a certain temperature within enclosed space at which humans are accustomed. Temperature is a physical property of a system that underlies the common notions of hot and cold something that is hotter generally has the greater temperature Room temperature is thus often indicated by general human comfort, with the common range of 18°C (64. The Celsius Temperature scale was previously known as the centigrade scale. 4 °F) to 24°C (75. Fahrenheit is a temperature scale named after Daniel Gabriel Fahrenheit (1686–1736 a German Physicist who proposed it in 1724 2 °F), though climate may acclimatise people to higher or lower temperatures. Climate encompasses the temperatures humidity rainfall atmospheric particle count and numerous other meteorogical factors in a given region over long periods of
The term can also refer to a temperature of food to be consumed (e. g. , red wine) which is placed in such a room for a given time. Furthermore, it may refer to a certain temperature within settings of scientific experiments and calculations.
For human comfort, desirable room temperature greatly depends on individual needs and various other factors. According to the West Midlands Public Health Observatory,[1] 21 °C (69. The West Midlands is a Metropolitan county in western central England with a population of 2591300 8 °F) is the recommended living room temperature, whereas 18 °C (64. 4 °F) is the recommended bedroom temperature. A study carried out at the Uppsala University,[2] on indoor air quality and subjective indoor air quality (SIAQ) in primary schools, states that perception of high room temperature was related to a poor climate of cooperation. Uppsala University ( Swedish Uppsala universitet) is a world-class research University in Uppsala, Sweden. Indoor Air Quality (IAQ deals with the content of interior air that could affect health and comfort of building occupants To achieve a good SIAQ, it recommends room temperature should be at a maximum of 24. 0 °C (75. 5 °F).
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Scientific definition
For scientific calculations, room temperature is taken to be 20 to 23. 5 degrees Celsius, 528 to 537 degrees Rankine (°R), or 293 to 296 Kelvin (K), with an average of 21 °C, about 70 degrees Fahrenheit (°F). The Celsius Temperature scale was previously known as the centigrade scale. Rankine is a thermodynamic (absolute temperature scale named after the Scottish Engineer and Physicist William John Macquorn Rankine The kelvin (symbol K) is a unit increment of Temperature and is one of the seven SI base units The Kelvin scale is a thermodynamic Fahrenheit is a temperature scale named after Daniel Gabriel Fahrenheit (1686–1736 a German Physicist who proposed it in 1724 [3]. For numerical convenience, either 20 °C or 300 K is often used. However, room temperature is not a precisely defined scientific term as opposed to Standard Temperature and Pressure, which has several, slightly different, definitions. In Physical sciences standard conditions for temperature and pressure are Standard sets of conditions for experimental measurements to allow comparisons to be made
Condition for physical experiments
The progress and results of many scientific and industrial processes depends a little or not at all on the temperature of the surroundings of the equipment. For example, a measurement of the charge of the electron does not depend upon the temperature of the test equipment. In such cases if any mention of temperature is made, it is customary and sufficient to speak simply of "room temperature", which essentially implies simply that what is being spoken of has not been specifically heated or cooled. Usually this means a temperature at which many people are comfortable, around 20 °C. In most cases considerable temperature variations are irrelevant; work may be carried out in winter or summer without heating or air-conditioning, without mention of the temperature. However, productivity is dependent on thermal comfort. Human thermal comfort is defined by ASHRAE as the state of mind that expresses satisfaction with the surrounding environment (ASHRAE Standard 55
The phenomena that researchers may choose to study at room temperature can naturally occur in the range of 20 to 23. Nature, in the broadest sense is equivalent to the natural world, physical universe, material world or material universe. 5 °C, or they may not. Researchers will choose to study a process outside its natural temperature range when they expect the conclusions to a specific question to be the same at room temperature as at a more natural temperature.
Experimentalists have an advantage in anticipating aspects of a room-temperature experiment, because the temperature is close to 20 °C (68°F, 527. 4 °R, 293 K), at which many of the material properties and physical constants in standards tables have been measured (more at standard state). A physical Constant is a Physical quantity that is generally believed to be both universal in nature and constant in time In Chemistry, the standard state of a material is its state at 1 bar (100 Kilopascals exactly By consulting such tables a researcher may estimate, for example, how fast a chemical reaction is likely to proceed at room temperature. A chemical reaction is a process that always results in the interconversion of Chemical substances The substance or substances initially involved in a chemical reaction are called
Unless there is a reason to work at a specific temperature, it is clearly more convenient not to control the temperature. Even in cases where a known, controlled, temperature is advantageous but not essential, work may be carried out at room temperature. But, for example, very large, warehouse-type experimental facilities may lack sufficient heating and cooling capabilities to maintain 'room temperatures'. HVAC (pronounced either "H-V-A-C" or occasionally " H-vak " is an Initialism or Acronym that stands for " Heating
If it is believed that work which may have some dependence upon temperature has been carried out at temperatures significantly outside the range 20 to 23. 5 °C, it may be reported that it was carried out at an ambient temperature of some approximate specified value.
An assumed typical ambient temperature may be used for general calculations; for example, the thermal efficiency of a typical internal combustion engine may be given as approximately 25%, with no mention of the air temperature: the actual efficiency will depend to some extent on ambient temperature, decreasing in extremely hot weather conditions due to lower air density. In Thermodynamics, the thermal efficiency (\eta_{th} \ is a dimensionless performance measure of a thermal device such as an Internal combustion
Ambient versus room temperature
Being an even less precise specification than "room temperature", "ambient temperature" is more certain to be accurate. Because scientists strive for accuracy in their reports, many use this specification exclusively just as a matter of course, even to describe experiments that they could justifiably characterize as having been conducted at room temperature.
This is a nebulous issue, depending upon the language used. In many languages, for example Spanish, there is no expression for "room", as distinct from "ambient", temperature.
Arguably, no precision is lost in this practice: in disciplines where experimenters always work in laboratories, and where temperature differences of a few degrees make little difference with regard to the questions that scientists ask, the distinction between ambient and room temperature literally is not worth making. And, of course, the ambient temperature of a room is usually room temperature.
Yet small temperature differences have large effects on many natural processes. Therefore scientists who do observe a distinction between the two specifications may be sticklers about which one to apply. For example, heat given off by electronics or motors may warm the area around an experiment relative to the rest of a room. Under such circumstances, and depending on the question under investigation, some scientists would consider it inaccurate to report that an experiment took place at room temperature.
See also
- Ambient food
- Psychrometrics — the study of moist air
- Standard temperature and pressure (STP)
References
- ^ Why more people die in the winter, by Michelle Roberts, Health reporter, BBC News
- ^ Dan Norbäck (1995) Subjective Indoor Air Quality in Schools - The Influence of High Room Temperature, Carpeting, Fleecy Wall Materials and Volatile Organic Compounds (VOC) Indoor Air 5(4), 237-246. Ambient food is Food which can be stored for long periods at Ambient temperature (21°C-70°F Refrigeration. Psychrometrics or psychrometry are terms used to describe the field of engineering concerned with the determination of physical and thermodynamic properties of gas-vapor mixtures In Physical sciences standard conditions for temperature and pressure are Standard sets of conditions for experimental measurements to allow comparisons to be made
- ^ The American Heritage Dictionary of the English Language, Fourth Edition. The American Heritage Dictionary of the English Language ( AHD) is an American Dictionary of the English language published by
Dictionary
room temperature
-noun
- A normal temperature of a room in which people live; typically 20 to 23°C; neither heated nor chilled.
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