ISO 7730
|
DIN EN ISO 7730 |
|---|---|
| Area | Metrology |
| title | Ergonomics of the thermal environment - analytical determination and interpretation of thermal comfort by calculating the PMV and PPD index and criteria of local thermal comfort |
| Brief description: | Ergonomics of thermal comfort |
| Latest edition | 2006-05 |
| ISO | 7730 |
The ISO standard 7730 is also called the comfort standard . It deals with the ergonomics of thermal comfort .
Thermal comfort (rating "0" or "neutral") is "the circumstance under which satisfaction with the thermal environment is expressed." There is a balance between the activity-related heat production of the human body and the current heat release to the environment, without the body having to perform special adaptations ("thermal stress"). The rating scale originally introduced by Ole Fanger for assessing thermal comfort is:
| rating | English | German |
|---|---|---|
| +3 | hot | hot |
| +2 | warm | warm |
| +1 | slightly warm | a bit warm |
| 0 | neutral | neutral |
| −1 | slightly cool | a little bit cold |
| −2 | cool | cool |
| −3 | cold | cold |
It turns out that the importance of the variables of the thermal field is the radiation temperature θ rmt , the air temperature θ a , the relative air speed v rel and the air humidity p a (water vapor partial pressure). The influence of humidity is very small under normal living space conditions and the air speed must be kept negligibly small (v <0.08 m / s) according to more recent findings. Against this background, the influence of temperature is crucial. As long as the air and radiation temperatures do not differ significantly (which they should not do in the interests of the additional comfort conditions), both temperatures can be converted to a "perceived" or "operative temperature" θ op
θ op = (θ a + θ rmt ) / 2
combine and formulate the requirements as requirements for this operational temperature. For rooms that are intended for the permanent stay of different people, the requirements for a high level of comfort (corresponding to PPD <6%) can be formulated:
- Fluctuations in the operative temperature in space and time:
- Δθ op = ± 0.8 K (max.)
- Limitation of the draft risk to DR <8%:
- v rel <0.08 m / s
- Radiation temperature asymmetry (ceiling / floor):
- Δθ r_ass <5 K
- Vertical difference in air temperature between the head and ankle of a seated person
- Δθ 1.1_0.1m <2 K
The total amount of still permissible changes in the operative temperature over time is also limited.
Another requirement relates to summer comfort in air-conditioned rooms; it is intended to ensure that the humid threshold is not exceeded: Systems that are intended to regulate humidity should be able to maintain a water vapor partial pressure below 1910 Pa (= 19.1 hPa) corresponding to a dew point temperature of 16.8 ° C.