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<DIV><SPAN class=000573514-05022008><FONT face=Arial size=2>Dear
All,</FONT></SPAN></DIV>
<DIV><SPAN class=000573514-05022008><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=000573514-05022008><FONT face=Arial size=2>I've recently coded
the equations in ASHRAE 55 (2004) for calculating PMV and PPD and cross
referenced these to ISO 7730:2005 (the reference ASHRAE gives). There are
several differences:</FONT></SPAN></DIV>
<DIV><SPAN class=000573514-05022008><FONT face=Arial size=2>1) line 250 - ASHRAE
has an extra factor of 6.45 in the equation</FONT></SPAN></DIV>
<DIV><SPAN class=000573514-05022008><FONT face=Arial size=2>2) line 300 - ISO
has (TRA/100)*4, ASHRAE (TRA/100)**4</FONT></SPAN></DIV>
<DIV><SPAN class=000573514-05022008><FONT face=Arial size=2>3) line 480 - ISO
has (TRA/100**4), ASHRAE has (TRA/100)**4</FONT></SPAN></DIV>
<DIV><SPAN class=000573514-05022008><FONT face=Arial size=2>4) line 520 - ISO
does not define a value for HL6 (ASHRAE has this on line
490)</FONT></SPAN></DIV>
<DIV><SPAN class=000573514-05022008><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=000573514-05022008><FONT face=Arial size=2>I believe that
difference (1) is unimportant as its setting the initial guess for an iterative
loop. However, for the other three differences I believe that ASHRAE is
correct and ISO has typos.</FONT></SPAN></DIV>
<DIV><SPAN class=000573514-05022008><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=000573514-05022008><FONT face=Arial size=2>I also have
differences in the output from the example cases. The differences
are:</FONT></SPAN></DIV>
<DIV><SPAN class=000573514-05022008><FONT face=Arial size=2>1) ASHRAE cases 3
and 6 give 11% PPD (the standard has 10%)</FONT></SPAN></DIV>
<DIV><SPAN class=000573514-05022008><FONT face=Arial size=2>2) ISO case 7 gives
8% PPD (the standard has 10%)</FONT></SPAN></DIV>
<DIV><SPAN class=000573514-05022008><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=000573514-05022008><FONT face=Arial size=2>The ASHRAE cases do
not concern me too much as the PMV is the same to one decimal place, but the PMV
in the ISO standard is quite different (0.50 in the std, 0.36 by my
calculations).</FONT></SPAN></DIV>
<DIV><SPAN class=000573514-05022008><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=000573514-05022008><FONT face=Arial size=2>Does
anyone:</FONT></SPAN></DIV>
<DIV><SPAN class=000573514-05022008><FONT face=Arial size=2>1) disagree with my
conclusions as to the differences in the printed code (i.e. you do not think ISO
has typos)?</FONT></SPAN></DIV>
<DIV><SPAN class=000573514-05022008><FONT face=Arial size=2>2) have any insights
as to the numerical differences (I think that there may be a typo in the ISO
standard)?</FONT></SPAN></DIV>
<DIV><SPAN class=000573514-05022008><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=000573514-05022008><FONT face=Arial
size=2>Thanks,</FONT></SPAN></DIV>
<DIV><SPAN class=000573514-05022008><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=000573514-05022008><FONT face=Arial
size=2>Iain</FONT></SPAN></DIV>
<DIV> </DIV>
<DIV align=left>
<DIV align=left><FONT size=1><FONT face=Arial><FONT color=#808080><SPAN
class=265514018-30052006>Dr. </SPAN>Iain Macdonald,
Ph.D.</FONT></FONT></FONT></DIV>
<DIV align=left><FONT face=Arial color=#808080 size=1>Research Officer / Agent
de recherches</FONT></DIV>
<DIV align=left><FONT face=Arial color=#808080 size=1>Indoor Environment
Research program / Programme de recherche sur l'environnement
intérieur</FONT></DIV>
<DIV align=left><FONT face=Arial color=#808080 size=1>Institute for Research in
Construction / Institut de recherche en construction</FONT></DIV>
<DIV align=left><FONT face=Arial color=#808080 size=1>National Research Council
Canada / Conseil national de recherches Canada</FONT></DIV>
<DIV align=left><FONT face=Arial color=#808080 size=1>1200 Montréal Road / 1200
chemin Montréal</FONT></DIV>
<DIV align=left><FONT face=Arial color=#808080 size=1>Ottawa Ontario K1A
0R6</FONT></DIV>
<DIV align=left><FONT face=Arial color=#808080 size=1>Phone/Tél: (613)
993-9676</FONT></DIV>
<DIV align=left><FONT face=Arial color=#808080 size=1>Fax: (613)
954-3733</FONT></DIV>
<DIV align=left><FONT face=Arial color=#808080 size=1>Email: </FONT><A
href="mailto:iain.macdonald@nrc-cnrc.gc.ca"><FONT face=Arial color=#808080
size=1>iain.macdonald@nrc-cnrc.gc.ca</FONT></A></DIV></DIV>
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