Network for Comfort and Energy Use in Buildings OpenAccess
This page is for any points of discussion members would like to raise … refer to TipsForEditing for advice on editing the page. Please date your entries …
Dear co-member, Recently I started a re-analysis of the Dutch standard for thermal comfort in train cabins (for train drivers, not passengers). Just for inspiration: are there any NCEUB colleagues that can mail me examples of local, national, international standards for thermal comfort in train cabins (apart from the standard UIC fiche 651)? What standards are used in train cabins for example in the US, Australia and Asia? Also: if anybody knows of interesting articles and studies I should look at (preferably both about comfort and performance effects of especially higher temperatures in cabins): let me know. Please mail any suggestion to: Atze Boerstra, email@example.com''
Thanks in advance,
Does anyone have any research results which throw light on problem we have with writing the new CIBSE Guide A1: Thermal comfort? The last CIBSE Guide A had the following: (in naturally ventilated buildings the temperature will be acceptable if) for sedentary areas such as offices an inside dry resultant temperature of 25°C is not exceeded for more than 5% of the annual occupied period (typically 125 hours). Do we know why 5% of the time is quoted? Is it based on any scientific results? Do we know anything about the Time/Discomfort interaction? Any information would be welcome.
Fergus Nicol, LEARN
Fergus, A widely used base criterion is max 90% satisfied during 90% of occupation time. So temperatures may be uncomfortable 10% of the occupation time, so 250 hours/year. Then assume that half of this is winter discomfort (too cold) and half is summer (too warm). That leaves 125 hours of warm discomfort per year. That's how 5% was chosen in the Netherlands. CIBSE may have used the same rationale.
Arjen Raue Cundall Australia
At the recent meeting Stuart Barlow quoted BRE Environmental Design Guide BR345, where it is stated that >29°C is unacceptable. Could not the authors of that guide throw some light on this issue.
Mike Holmes Arup.
There is an issue about the inclusion of short wave radiation (solar) in the calculation of the mean radiant temperature for the calculation of a comfort temperature. Research at Loughborough and theoretical (Fanger) based calcs suggest an increase of about 1 PMV for each 200w/sq.m falling on the subject. Therefore omission is likely to underestimate discomfort at air temperatures when heating is not required. Current proposals for Guide A1 follow that convention - surely we should be thinking about making things more realistic. Is the research there?
Mike Holmes Arup.