Abstract The current design standard BS EN ISO7730 [Moderate thermal environments—determination of the PMV and PPD indices and specification of the conditions for thermal comfort, International Standards Organisation (1995)] is based upon the work of Fanger, and essentially comprises a steady-state human heat balance model that leads to a prediction of the sensation of human thermal comfort for a given set of thermal conditions. The model was derived from laboratory-based measurements conducted in the mid-1960s in relatively ‘conventional’ environments. However, a chilled ceiling operated in combination with displacement ventilation represents a more sophisticated environment as compared with the original conditions in which the Fanger model was derived. This raised a question about the applicability of the current standard when designing for thermal comfort in offices equipped with chilled ceiling/displacement ventilation systems. This paper presents findings from an EPSRC-funded study that sought to answer the above question. Human test subjects (184 in total) carried out sedentary office-type work in a well-controlled environmental test room that simulated an office fitted with the above system. Measurements of environmental variables were taken at a number of locations near the subjects, each of whom wore a typical office clothing ensemble. The reported thermal comfort sensations were compared with values predicted from BS EN ISO7730 over a range of system operating conditions. It was shown that the current standard BS EN ISO7730 may be used, without modification, when designing for the thermal comfort of sedentary workers in offices equipped with chilled ceiling/displacement ventilation systems. These findings are interpreted within the context of a proposed modification to thermal comfort design standards that includes adaptive effects, and the influence of BS EN ISO7730 on the development of other radiant surface/displacement ventilation configurations is discussed.
[1]
Tatsuo Nobe,et al.
Floor-supply displacement air-conditioning: Laboratory experiments
,
1999
.
[2]
Gail Brager,et al.
A Standard for Natural Ventilation
,
2000
.
[3]
Fred Bauman,et al.
Individual thermal comfort control with desk-mounted and floor-mounted task/ambient conditioning (TAC) systems
,
1999
.
[4]
M.G.L.C. Loomans.
Study on the applicability of the desk replacement ventilation concept
,
1999
.
[5]
Qingyan Chen,et al.
A critical review of displacement ventilation
,
1998
.
[6]
Dennis L. Loveday,et al.
Thermal comfort in chilled ceiling and displacement ventilation environments: vertical radiant temperature asymmetry effects
,
1998
.
[7]
Dennis L. Loveday,et al.
Designing for thermal comfort in combined chilled ceiling/displacement ventilation environments
,
1998
.
[8]
Mats Sandberg,et al.
Discomfort due to Vertical Thermal Gradients
,
1996
.
[9]
Bjarne W. Olesen,et al.
Evaluation of a vertical displacement ventilation system
,
1994
.
[10]
S. Holst,et al.
Using radiant cooled floors to condition large spaces and maintain comfort conditions
,
2000
.
[11]
R. Dear,et al.
Thermal adaptation in the built environment: a literature review
,
1998
.
[12]
Takashi Akimoto,et al.
Experimental study on the floor-supply displacement ventilation system
,
1995
.
[13]
P. Fanger.
Moderate Thermal Environments Determination of the PMV and PPD Indices and Specification of the Conditions for Thermal Comfort
,
1984
.