I just re-read Nadja Turek's earlier comment (from Aug 29, 2012) which included this excerpt from a CIR response:
"The metabolic rate for occupants involved in highly physically activity fall outside the range governed in the standard, therefore, thermal comfort conditions must be based on acceptable practices. The project should utilize an alternative compliance method or extrapolation of existing data to show compliance with the
credit for the spaces which fall outside the range of standard 55-2004.
ASHRAE 55-2010 has a revised computer simulation method which accommodates MET levels up to 5.0."
The problem is, ASHRAE 55-2010 specifically states that only rates between 1.0 and 2.0 MET fit within the PMV-PPD model, and only 1.0-1.3 MET for the adaptive model (see section 5.2.1.2, 5.3 and Appendix A).
The ASHRAE Thermal Comfort Tool v2 software (which follows ASHRAE 55-2010) allows an input value up to 5.0 MET... but it also generates a notice that this rate is not covered by the standard, if you try to enter anything above 2.0 MET. It seems to me whoever responded to Nadja's CIR misunderstood that.
Does anyone have a project that achieved this credit with spaces that fell outside of ASHRAE 55 parameters? Has any direction been given for alternate compliance? James Del Monaco posted his discussion with a reviewer back in Nov 2010, but it seems many are still looking for clarification on this.
Anthony Hardman
Building Performance AnalystThe Green Engineer
16 thumbs up
March 25, 2013 - 11:09 am
I have the same understanding. GBCI shouldn't be asking project teams to comply with ASHRAE 55 when the conditions clearly fall outside the boundaries of the standard. CIR's aren't precedent setting anyway, so I would ignore this and simply state the exception to the standard from Appendix A.
Scott Bowman
LEED FellowIntegrated Design + Energy Advisors, LLC
LEEDuser Expert
520 thumbs up
April 17, 2013 - 11:54 am
We have been successful excluding zones in some projects that are not covered by ASHRAE 55, and that were outside the bounds of the standard with MET > 2.0. At that point we do include some narrative on what we did to address that condition, and what the standard of practice was for those zones. For example, ceiling fans in a fitness room to increase air movement over machines.