AIVC #13,671
ASHRAE Journal
'
Ventilation for Enclosed Parking Garages By Moncef Krartt, Ph.D., P.E., and Arselene Ayarl, Ph.D. Member ASHRAE
indication of risks from exposure
pen l:!arng
s ar
A and g ncra l l d n t n
·
foh!c I.
typically above-grade \Vith open sides
Thi.: ventilation rate re4uireml.'nts rec
other codes ;ire in
few well-rounded points: I flow aver I 000 cfm-r spcci;il cv..:nts.
�- The l c \' cl of CO concentration acceptable within the ga
rage, co,,,_,, (ppm).
5. Total
I. Dctcrn1inc the peak gener.itiLm rate. GR (gr hr m : [gd1r·tF ]),
for the Equation
-
parking
I:
garage
per
unit
lloor
area
R..
...
within
thc garage in
Consider a two-le\'cl cnc l nsed parking gari . gc with a total
capacity of450 cars,
a
total
tlt'l\)r :irea of K9.300
ff ( �300 rn'). and
an a\erage height of9 n !2.75 ml. The total length of time for a typic1l
car
opcration is two minutes ( 120
s). Dct.:rrnine
the re
quired\ cnti lation rat..: for th.: enclosed parking garage in L's·m:
and in
ACH
so
sume t hat the
that the CO
numhcr
never exceeds 25 ppm. As
lcvds
of cars in operation is .+O';'n of the Cota I
vd1iclc capacity (a shopping mall fat:ility).
Step I. Garage data: .V=450 x 0.4 180 cars, ER=11.66 gnnin (averag1: emi ssion rate for a winter day u s ing the data from fohle 3). T = 120 s, CO..,.,= 25 ppm.
using
Step 2.
(a)
/'=�xlOO
NEW
..
=
tloor area llfthe parking area. A, (rn:).
Step2.
f(·s) f(.ir co ,., =35 ppm
and Tis the average tra\ cl timi.: of c:irs
.:stimat..: ('()emission ratcs for a typii.:al car. Ty pii.:;illy. hot �tarts
arc common in facilities when: cars arc rarked for shl)rt rcrinds such as shupping mal l s. \kanwhilc. cold starts eharactc1izc
'L:m:-s: (2J70x 1 O "cfnvtF·s) for CO'""=15 ppm
C alcu l ati.: CO generation rate:
(.,1,
,
�.
·-
(I)
180 11.66
gr min
()( ) n in h
------='----..,..----- = lOOO 111
Automated Commercial HVAC Design
J
(b) Step
.
3.
=
15.17
--
x
26.8
15.1 i gr/h,111
100
=0
56.6
Di.:tennin..: the ventilation re
Drawing: Right-CommDraw Df � & drop s.rNrt HVAC \h.ape1 fot tan de1>1gn �e.id.Mlnte AutoCADtm DWG .:ind OXF hh.'1 tor eouy 1ntir:rf�e
quirement:
loads:
for CO..,,, =25
Using the corrcbtion of Equation
Rlght-Commload
ASHRAE 14 hour method, H;ant:lbook of F\md.am""ntJJ\
ppm. the
tion r..1h: in Us·m2
can
3
design ven tila
be calculated:
Ducts: Right-CommDuct
ASHRAf Duct F1nin9 Oat.>B�e 'lllo1th �tal1C Regam, Equ.ti Friction
wnghtsoft""
Proposal: Right-CommProposal Ma:i1m1zt prof1t,,bil1ry b� 9ent-t'1t1n9 1tli�t .tnd dlaT /:} .: ..·I VS/ . IS/ IR I {Stum/ard f>:}-f'J89, I °i'11ttl.11i1111 /i1r. lcn:p1aN1· In door .·1ir Q11a!itl'. 3. 1\yari. :\ . IL\ Grot. \1. Kr;ini. 2000. "Field cvaluatit'n llf h'll ulation -,ystcm rx·rformancc· in cncl11>cd rari...ing garngcs,"' :ISf/R If Tums1w1io111·. I 06( I) .+. Krarti. M . :\ Ayari.
