ASHRAE Journal - June 2024 - 53

TECHNICAL FEATURE
starts declining and reaches zero at about 21 minutes,
which is the Purge Time (PT)25. It means at this time the
concentration levels in the breathing zone are below the
threshold value of 25 ppm.
With the activation of DCV and increase in the supply
airfl ow rate, the peak (SI)BZ25value reduces to 25.9% and
reaches its peak value after 9.5 minutes-3.5 minutes
sooner than the case without DCV. After the release of
vapor stops at 12 minutes the (SI)BZ25value shows a sharp
decline. Similarly, with the DCV the Purge Time (PT)25
value reaches zero at about 14 minutes-seven minutes
sooner than the case without DCV. Enhanced airfl ow rate
increases the dilution, and the enhanced ach increases
the rate of depletion
(removal). It should be
noted that the effect of
DCV is realized after two
minutes of initiation
when the (SI)BZ25value
starts decreasing. This
fi gure shows the impact
of both the dilution due to
increased airfl ow rate and
the rate of removal due to
increased ach.
6
5
4
3
2
1
Analysis of Chemical
Exposure (Dose)
Figures 7a through 7c show
variations of concentration
with time in front of each
person's face as detected
by the virtual sensors
along with the associated
exposure. The impact
of DCV on individual
exposure depends on the
location of a person. In the
case of Person 1 (Figure 7a),
who is located away from
the source, the initial
concentration level and
the resulting cumulative
exposure increased with
the initiation of DCV.
Higher airfl ow rates
associated with higher air
25
20
15
10
5
velocities enhanced the transport of vapors within the
space. After the initiation of DCV, the concentration
level in front of Person 1 increases rapidly and starts
declining only after 20 minutes-14 minutes after the
initiation of DCV.
In the case of Person 2 (Figure 7b), located next to the
spill (source), the enhanced dilution due to increased
airfl ow rate helped in reducing the concentration level
as well as the cumulative exposure. However, such
reduction in the cumulative exposure is realized only
after 16 minutes-10 minutes after the initiation of DCV.
It means during the fi rst 16 minutes of DCV there is no
benefi cial impact on the exposure of Person 2.
FIGURE 7A Variation of contaminant concentration and associated exposure with time for Person 1 showing the impact of DCV.
Without DCV
With DCV
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30
Time (minutes)
Concentration
60
50
40
30
20
10
Without DCV
With DCV
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30
Time (minutes)
Exposure
FIGURE 7B Variation of contaminant concentration and associated exposure with time for Person 2 showing the impact of DCV.
Without DCV
With DCV
250
200
150
100
50
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30
Time (minutes)
Concentration
Without DCV
With DCV
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30
Time (minutes)
Exposure
FIGURE 7C Variation of contaminant concentration and associated exposure with time for the Person 3 showing the impact of DCV.
30
25
20
15
10
5
Without DCV
With DCV
400
350
300
250
200
150
100
50
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30
Time (minutes)
Concentration
Without DCV
With DCV
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30
Time (minutes)
Exposure
J U N E 2 0 2 4 ashrae.org ASHRAE JOURNAL
53
Concentration (ppm)
Concentration (ppm)
Concentration (ppm)
Exposure (ppm-min)
Exposure (ppm-min)
Exposure (ppm-min)
http://www.ashrae.org

ASHRAE Journal - June 2024

Table of Contents for the Digital Edition of ASHRAE Journal - June 2024

Contents
ASHRAE Journal - June 2024 - Intro
ASHRAE Journal - June 2024 - CT1
ASHRAE Journal - June 2024 - CT2
ASHRAE Journal - June 2024 - Cover1
ASHRAE Journal - June 2024 - Cover2
ASHRAE Journal - June 2024 - 1
ASHRAE Journal - June 2024 - Contents
ASHRAE Journal - June 2024 - 3
ASHRAE Journal - June 2024 - 4
ASHRAE Journal - June 2024 - 5
ASHRAE Journal - June 2024 - 6
ASHRAE Journal - June 2024 - 7
ASHRAE Journal - June 2024 - 8
ASHRAE Journal - June 2024 - 9
ASHRAE Journal - June 2024 - 10
ASHRAE Journal - June 2024 - 11
ASHRAE Journal - June 2024 - 12
ASHRAE Journal - June 2024 - 13
ASHRAE Journal - June 2024 - 14
ASHRAE Journal - June 2024 - 15
ASHRAE Journal - June 2024 - 16
ASHRAE Journal - June 2024 - 17
ASHRAE Journal - June 2024 - 18
ASHRAE Journal - June 2024 - 19
ASHRAE Journal - June 2024 - 20
ASHRAE Journal - June 2024 - 21
ASHRAE Journal - June 2024 - 22
ASHRAE Journal - June 2024 - 23
ASHRAE Journal - June 2024 - 24
ASHRAE Journal - June 2024 - 25
ASHRAE Journal - June 2024 - 26
ASHRAE Journal - June 2024 - 27
ASHRAE Journal - June 2024 - 28
ASHRAE Journal - June 2024 - 29
ASHRAE Journal - June 2024 - 30
ASHRAE Journal - June 2024 - 31
ASHRAE Journal - June 2024 - 32
ASHRAE Journal - June 2024 - 33
ASHRAE Journal - June 2024 - 34
ASHRAE Journal - June 2024 - 35
ASHRAE Journal - June 2024 - 36
ASHRAE Journal - June 2024 - 37
ASHRAE Journal - June 2024 - 38
ASHRAE Journal - June 2024 - 39
ASHRAE Journal - June 2024 - 40
ASHRAE Journal - June 2024 - 41
ASHRAE Journal - June 2024 - 42
ASHRAE Journal - June 2024 - 43
ASHRAE Journal - June 2024 - 44
ASHRAE Journal - June 2024 - 45
ASHRAE Journal - June 2024 - 46
ASHRAE Journal - June 2024 - 47
ASHRAE Journal - June 2024 - 48
ASHRAE Journal - June 2024 - 49
ASHRAE Journal - June 2024 - 50
ASHRAE Journal - June 2024 - 51
ASHRAE Journal - June 2024 - 52
ASHRAE Journal - June 2024 - 53
ASHRAE Journal - June 2024 - 54
ASHRAE Journal - June 2024 - 55
ASHRAE Journal - June 2024 - 56
ASHRAE Journal - June 2024 - 57
ASHRAE Journal - June 2024 - 58
ASHRAE Journal - June 2024 - 59
ASHRAE Journal - June 2024 - 60
ASHRAE Journal - June 2024 - 61
ASHRAE Journal - June 2024 - 62
ASHRAE Journal - June 2024 - 63
ASHRAE Journal - June 2024 - 64
ASHRAE Journal - June 2024 - 65
ASHRAE Journal - June 2024 - 66
ASHRAE Journal - June 2024 - 67
ASHRAE Journal - June 2024 - 68
ASHRAE Journal - June 2024 - 69
ASHRAE Journal - June 2024 - 70
ASHRAE Journal - June 2024 - 71
ASHRAE Journal - June 2024 - 72
ASHRAE Journal - June 2024 - Cover3
ASHRAE Journal - June 2024 - Cover4
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_FYONLJ
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2024november_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2024november
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_BDMHLG
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_WJDGRY
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_ATMAHK
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_VHQRAW
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_XGMDXI
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_YELQLJ
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_QJLWMC
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_MCDEBX
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_WNYSQY
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_XATVOD
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_FJSHSS
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_CCBZDS
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_XDEFVG
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2023november_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2023november
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_VHGNBL
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_WPKBNJ
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_UUVCDE
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_RTGDEW
https://www.nxtbook.com/nxtbooks/ashrae/ashraemexico_2023
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_LKRFXS
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_AZSOFG
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_ERCDBH
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_QWDFRV
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_JHGVDF
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_OPUYHG
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_SREIBM
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_LRTGLK
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_OKRFGH
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2022november_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2022november
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_TZSERA
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_LVRUIX
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_RPTVYZ
https://www.nxtbook.com/nxtbooks/ashrae/mini_pub_catalog
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_XIYTGD
https://www.nxtbook.com/nxtbooks/ashrae/ashraemexico_2022
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_RFGDOB
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_PABXNU
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_REMKLS
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_PICVBT
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_AOYTVW
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_JQOPLS
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_IOYTBC
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_SGAJJF
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_IGHYER
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_PDRKLS
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2021november
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2021november_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_XCODFR
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_QSLFGO
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_ILKVNM
https://www.nxtbook.com/nxtbooks/ashrae/ashraemexico_2021
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_OPDJKD
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_VJKSRY
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_SDHUTC
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_JPPKRR
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_SDLTTH
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_CKLLES
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_SLDOX
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_HJETUK
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_OLUHGE
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2020october
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2020october_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_ZERDGH
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_QVMNEO
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_RTPOKE
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_BBATRE
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_STUBMW
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_TPEMPE
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_JNMKDS
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_FBTTPA
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_WQMMNE
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_TVBRYN
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_showguide2020
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_KTUZMA
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_ABEDGD
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201910
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201909
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2019septmeber_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2019september
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201908
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201907
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201906
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201905
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201904
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_2019april
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201903
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_2019march
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201902
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201901
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_showguide2019
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_2018december
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_2018november
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2018fall_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2018fall
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_2018october
https://www.nxtbook.com/nxtbooks/ashrae/ashraemexico_2018
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201810
https://www.nxtbook.com/nxtbooks/ashrae/ashraeinsights_201806
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201805
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201804
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201803
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201712
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201711
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201710
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2017fall_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2017fall
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201709
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201705
https://www.nxtbook.com/nxtbooks/ashrae/ashrae_meetinginsert_201610
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2016fall_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2016fall
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_acrexindia
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2015summer_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_amca_2015summer
https://www.nxtbook.com/nxtbooks/amca/2014summer2
https://www.nxtbook.com/nxtbooks/amca/2014summer
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_acma_2014summer
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201311
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201309
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_acmasupp_2013fall
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201305
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201303
https://www.nxtbook.com/nxtbooks/ashrae/pubcatalog_2013winter
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201211
https://www.nxtbook.com/nxtbooks/ashrae/achr_expo_mexico2012
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201209
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201208_v3
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201208_v2
https://www.nxtbook.com/nxtbooks/ashrae/pubcatalog_2012summer
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201205
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201203
https://www.nxtbook.com/nxtbooks/ashrae/pubcatalog_2012winter
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201111_v2
https://www.nxtbook.com/nxtbooks/ashrae/ashraejournal_201109_v2
https://www.nxtbook.com/nxtbooks/ashrae/pubcatalog_2011summer
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201105
https://www.nxtbook.com/nxtbooks/ashrae/meetingplanner_201103
https://www.nxtbookmedia.com