ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 11
Improving Upper-Room UV With Ceiling Fans
By DAVID ROSE
Studies show that, in spaces with limited air mixing,
natural convection generated by heat gains from
occupants and equipment at the floor level can
reduce the effectiveness of upper-room/air UV
systems. In such instances, the use of ceiling fans
for air mixing has been shown to increase UV
effectiveness by more than 60 percent.1
This is especially true in the case of facilities
with high ceilings, where even HVAC systems with
high airflow rates can struggle with air mixing and
distribution. This issue is particularly problematic
during the heating season, when the rate of illness
among occupant populations tends to be the
highest.
With ceiling fans, the volume of air that is actively
Lighting simulation showing upper-room-UV fluence
rates (red = 10 uW/cm2, dark blue = 5 uW/cm2, light
blue = 1 uW/cm2).
cleaned in the disinfection zone is more frequently
circulated back to the occupant level and replaced
in the disinfection zone with air that has a higher
concentration of contaminants. With continual mixing
of the disinfection-zone and occupant-breathing-zone
air volumes, the effectiveness of the upper-room/
air system is improved, increasing the effective airchange rate. This effect reduces the concentration
of contaminants in the space without the need for
a three- to six-time increase in outdoor-air-change
rate. Once the space air is well-mixed, additional
air turnovers are not likely to increase system
effectiveness.2
References
1) Ko, G., First, M.W., & Burge, H.A. (2002). The characterization of
Computational-fluid-dynamics image tracing
exposure of particles to upper-room UV-C lamps
upper-room ultraviolet germicidal irradiation in inactivating airborne
(purple rectangles in the upper right and center of
microorganisms. Environmental Health Perspectives, 110, 95-101.
the image) with the use of large- and small-diameter
2) Rudnick, S.N., McDevitt, J.J., Hunt, G.M., Stawnychy, M.T.,
ceiling fans. Small-diameter ceiling fans integrated
Vincent, R.L., & Brickner, P.W. (2015). Influence of ceiling fan's speed
with UV-C lamps are not visible. The height of the
and direction on efficacy of upper-room, ultraviolet germicidal irradia-
large-diameter fan is 18 ft 4 in.; the heights of the
tion: Experimental. Building and Environment, 92, 756-763.
small-diameter fans are 10 ft 4 in. and 9 ft 3 in.
About the Author
David Rose is applications engineering manager for Big Ass Fans. He can be contacted at info@bigassfans.com.
w w w. a m c a .o r g
2020 A M CA i n m o t i o n
11
http://www.amca.org
ASHRAE Journal Supplement - AMCA InMotion - October 2020
Table of Contents for the Digital Edition of ASHRAE Journal Supplement - AMCA InMotion - October 2020
Contents
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - BB1
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - BB2
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - Cover1
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - Cover2
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - Contents
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 2
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 3
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 4
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 5
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 6
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 7
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 8
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 9
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 10
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 11
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 12
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 13
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 14
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 15
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 16
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 17
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 18
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 19
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 20
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 21
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 22
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 23
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 24
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 25
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 26
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 27
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 28
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 29
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 30
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 31
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 32
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 33
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 34
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 35
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 36
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 37
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 38
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 39
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 40
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 41
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 42
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 43
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - 44
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - Cover3
ASHRAE Journal Supplement - AMCA InMotion - October 2020 - Cover4
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