The Adaptive Model of Thermal Comfort: University of Sydney's ASHRAE RP-884 Project

Introduction to the Project

The American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE Inc.) commissioned Dr Richard de Dear of The University of Sydney to develop and adaptive model of thermal comfort during 1995-1997. Dr Gail Brager of CEDR, University of California at Berkeley collaborated on this project.

The Adaptive Model Concept


The human body maintains thermal equilibrium with its environment by means of phsyiological thermoregulation (sweating, shivering etc). Beyond these automatic processes, there is a suite of adaptive responses which enable building occupants to adapt to indoor and outdoor climates by means of behavioral adjustments ((clothing, windows, fans etc), physiological adaptations (acclimatisation), and psychological adjustments (expectations). Click this link to see a schematic describing the adaptive model concept and how it relates to energy consumption in buildings.

The ASHRAE RP-884 Database

A grand total of about 22,000 sets of data have been included inthe RP-884 database at the time of writing. Click this link to go to the RP-884 Adaptive Model Database Downloader. There you'll be able to obtain copies of the raw data files that constitute this database. But before attempting to use this tool you should read through (and print a copy of) the following points carefully.

  • Data Assimilation: The processes of data acquisition and assimilation into the RP-884 database are explained in the following flow chart.
  • Contents and Structure of the data Files: Each of the individual files has a standard structure, with each row representing a response (questionnaire, indoor climatic measurements, clo and met, comfort indices etc). Click this link to see the "codebook" which describes the varaibles' names, their units of measurement and the various coding conventions adopted throughout the database. This information should be printed.
  • Project Summaries: The "data downloader" will appear in you net browser as a clickable table. The column entitled "Researchers and Publications" is linked to short descriptions of the buildings, locations, samples, instruments and procedures used in each field research project as well as some citations so you you can read more about the original research. This information should be printed.
  • Location and Climate Zone: The "data downloader"contains information on the geographic location and the climate zone for each of the data files in the RP-884 database.
  • Digital File Format: data in the RP-884 "data downloader" can be downloaded as EXCEL 5 spreadsheets.
  • Acknowledgments: If you intend using the research data contained in this database, please ensure that you give appropriate acknowledgment to the original field researchers (see project summaries for citation details). Please also acknowledge Richard de Dear for assembling, cleaning and standardising the database, and making it available on the WWW with financial support from ASHRAE Inc. This paper, ASHRAE Transactions describes the database and should be cited:
    de Dear, R.J. (1998) "A global database of thermal comfort field experiments," ASHRAE Trans, V.104(1)
    This web site may be acknowledged by reference to the URL details printed in the footer below.

Results from the ASHRAE RP-884 Adaptive Model Project

Preliminary results from the adaptive model project have been formatted as a series of linked WWW pages which you can read by clicking here. More detailed results and interpretations can be found in the RP-884 ASHRAE Technical Paper:

de Dear R.J. and G.Schiller Brager (1998) "Developing an adaptive model of thermal comfort and preference," ASHRAE Trans., V.104(1a), pp.145-167. Reprinted in Schiller Brager, G. (ed.) (1998) Field Studies of Thermal Comfort and Adaptation - ASHRAE Technical Data Bulletin, V.14(1). pp. 27-49.

de Dear, R.J. (1998) "A global database of thermal comfort field experiments," ASHRAE Transactions., V.104(1b), pp.1141-1152. Reprinted in Schiller Brager, G (ed.) (1998) Field Studies of Thermal Comfort and Adaptation - ASHRAE Technical Data Bulletin, V.14(1). pp. 15-26.

Schiller Brager, G. and R. de Dear (2000) "A standard for natural ventilation." ASHRAE Journal. V.42(10), pp.21-27.

Brager, G.S. and de Dear, R.J. (1998) "Thermal adaptation in the built environment: A literature review," Energy and Buildings, V.27(1), pp.83-96.

You may also be interested in downloading the full PDF version of the Final Report (ca 1.8Mb) on this project by clicking here.

While you are here you may wish to visit the WWW Thermal Comfort Index Calculator.

The calculator was programmed in JavaScript from the original sourcecode supplied in the ISO7730 Standard and also the software by Fountain and Huizenga, 1996 (WinComf). It calculates clo values, PMV, PPD, ET*, SET*, DISC, COMF, PD etc.

Useful Links