(Supersedes ANSI/ASHRAE Standard ). Thermal. Environmental. Conditions for. Human Occupancy. Approved by the ASHRAE Standards Committee. See Appendix I for approval dates by the ASHRAE Standards Committee, the ASHRAE an ASHRAE Standard may be purchased from the ASHRAE Web site . This standard is in close agreement with ISO Standards and Page 1 ANSI/ASHRAE Standard R Public Review Draft Table of Contents 1.
|Published (Last):||27 September 2017|
|PDF File Size:||5.93 Mb|
|ePub File Size:||4.25 Mb|
|Price:||Free* [*Free Regsitration Required]|
This optional method is intended for such spaces.
If any other version is used, it is the user’s responsibility to verify and document that the version used yields the same results as the code in Appendix D for the conditions asnrae which it is applied. Percentage of dissatisfied due to local discomfort from various sources for different classes of thermal environment.
It 55-19922 be expressed in terms of several thermodynamic variables including vapor pressure, dew point temperature, and humidity ratio. Typical examples might be near windows, diffuser outlets, corners, and entries.
ASHRAE 55 – Wikipedia
The values of PPD predicted from this equation must be within the limits specified for draft in Table 5. Humidity is a general reference to the moisture content of the air. If the occupant is moving, it also affects the insulation value of clothing. It is acceptable to interpolate between curves for intermediate differences. All informative background information has been moved to informative appendices.
And this equation is only valid when the metabolic rate is between 1. Since floor temperatures seldom change rapidly, time averaging does not need to be considered. Adaptive asyrae is a model that relates indoor design temperatures or acceptable temperature ranges to outdoor meteorological or climatological parameters.
The surface area of an average person is 1. Values assumed for comfort parameters, including clothing and metabolic rate, used ashae calculation of design temperatures, shall be clearly stated 2. The less extreme conditions include both internal loads and the external environment. This specific upper humidity limit may result in condensation on building surfaces. Looking for previous revisions of this standard? At the completion of the survey, the survey sheets and analysis of the data shall be turned ashtae to the design engineer and the owner for review and sign-off of the commissioning process.
A time-weighted average metabolic rate may be used for individuals with activities that vary over a period of one hour or less. A complete clothing ensemble may qshrae defined using a combination of the garments listed in Table B2. The designer may choose in agreement asshrae the builder the thermal comfort class. Clothing insulation is the resistance to sensible heat transfer provided by a clothing ensemble expressed in units of clo, which is a unit to 55-992 the insulation provided by garments and clothing ensembles.
Air speed is the average speed of the air to which the body is exposed. The graph is valid for prevailing mean temperatures between 10— In general, body motion decreases the clothing insulation by pumping air through clothing. Each application of commissioning for thermal comfort is unique.
Standard 55 – Thermal Environmental Conditions for Human Occupancy
The first method of environment commissioning is to statically determine occupant satisfaction through the evaluation of survey results. This schedule should be documented per section 6.
The combinations of air speed and temperature defined by the lines in this figure result in the same heat loss from the skin. Therefore the elevated air speed must be under the direct control of the affected occupants and adjustable in steps no greater than 0. As a minimum, the temporal average ashdae a three-minute average with at least 18 equally spaced points in time.
ASHRAE 55 1992
When no measurement of turbulence intensity is required, the time constant of the device used to measure air speed is allowed to be longer.
While this concern is beyond the scope of this standard, moisture on surfaces can lead to biological contamination and damage to building components. Comfort zone refers to the combinations of air temperature, mean radiant temperature trand humidity that are predicted to be an acceptable thermal environment at particular values of air speed, metabolic rate, and clothing insulation I cl .
Retrieved from ” https: Any application of this standard must specify the space to which it applies and the locations within that space to which it applies if not the entire space. The environmental conditions required for comfort are not the same for everyone. It was revised in,and For the purpose of Section 5, mean radiant temperature is also a time-averaged value.
Table Bl lists the insulation provided by a variety of common clothing ensembles. For satisfaction surveys, the thermal satisfaction scale shall end with choices: The people occupying a particular space at a particular time may happen to prefer a lower or a higher temperature level than shown in Figure 5. It is defined as per unit of skin surface area which equals to It is spatially and temporally averaged in the same manner as air temperature.
Except sedentary activities, metabolic rate for all other activities is likely to have range of variation. In the standard underwent significant changes with the addition of two thermal comfort models: Allowable cyclic operative temperature variation.
Sample documentation is provided in Informative Appendix J.
The plane radiant temperature is defined similarly to mean radiant temperature except that it is with respect to a small planar surface element exposed ashrxe the thermal radiation from surfaces from one side of that plane.
Therefore, an effective way to evaluate the environmental conditions is to survey the occupants.