NOTE: In this
psychrometric chart
the abscissa is the dry-bulb temperature, and the mean radiant temperature (MRT) is fixed, controlled by
the inputbox. Each point on the chart has the same MRT, which defines the comfort zone boundary. In this way you can see how changes in MRT
affect thermal comfort. You can also still use the operative temperature button, yet each point will have the same MRT.
Limits of Applicability: This standard is only applicable to healthy men and women.
This standard does not apply to occupant: a) whose clothing insulation exceed 1.5 clo; b) whose clothing is highly
impermeable; or c) who are sleeping, reclining in contact with bedding, or able to adjust blankets or bedding.
NOTE: In this
psychrometric chart the
abscissa is the operative temperature and for each point dry-bulb temperature equals
mean
radiant
temperature (DBT = MRT). The comfort zone represents the
combination of conditions with the same DBT and MRT for which the PMV is between -0.5
and
+0.5,
according to the standard.
Limits of Applicability: This standard is only applicable to healthy men and
women.
This standard does not apply to occupant: a) whose clothing insulation exceed 1.5 clo;
b)
whose
clothing is highly
impermeable; or c) who are sleeping, reclining in contact with bedding, or able to
adjust
blankets
or bedding.
NOTE: This chart represents only two variables, dry-bulb temperature and relative
humidity.
The PMV calculations are still based on all the psychrometric
variables, but the visualization becomes easier to understand.
NOTE: This chart represents only two variables, air speed against operative
temperature.
The
operative temperature for each point is determined by
dry-bulb temperature equals mean radiant temperature (DBT = MRT). The calculation of PMV
comfort
zone is based on all the psychrometric variables, with PMV
values between -0.5 and +0.5 according to the standard.
Limits of Applicability: The elevated air speed comfort zone method is to all
spaces
where
the occupants have
activity levels between 1.0 and 2.0 met and clothing insulation between 0.0 and 1.5 clo.
There is no upper limit to air speed if occupant's
total clothing > 0.7 clo and metabolic rate > 1.3 met.
