ASHRAE Journal - September 2019 - 10

LETTERS

which allows for reduction of outside air from standard ventilation
rates. The fact is prior to and subsequent to this testing; the 403.2
exception has not been allowed
in New York State Education
Department.
Corona discharge is just one form
of an ionization process and one
type of an electronic air cleaner.
There are many types of these technologies, and they have been used
in literally 10,000-plus applications
in schools across the U.S. over the
past 20 where the 403.2 exception was applied. No IAQ issues
have ever been reported from any
of these applications, and these
schools have benefitted from lower
HVAC equipment and conditioning
costs plus good IAQ in those treated
spaces. Many studies with findings
of improved IAQ using electronic air
cleaning products have been done.
It is our position that the testing
the column was based on was poorly
constructed. It lacked an adequate
baseline and an outdoor air comparison. The column then makes statements based on this flawed test. This
column would leave the reader with
more questions than answers.

Anthony M. Abate, Member ASHRAE, Fairfield, Conn.

The Authors Respond
Thank you for asking New York
State Department of Health
(Department) to respond to the
most recent letter regarding our column in the December 2018 issue of
ASHRAE Journal.
The Department determined
that increases in concentrations of
aldehydes and ultra-fine particles
resulted from operating the corona
discharge air cleaner in the classroom
by comparing the concentrations
10

ASHRAE JOURNAL

ashrae.org

during periods when the corona discharge was turned on to periods when
it was turned off. The data, summarized in Table 1 and Figure 2 in the
column, show that the concentrations
of aldehydes and ultra-fine particles
were consistently higher when the
corona discharge was operating.
Data collected by the New York
State Department of Environmental
Conservation (data available upon
request) shows hourly, average
ozone concentrations ranged from
21 to 38 parts per billion (ppb) at
the outdoor ozone monitor nearest
the school during the study period,
Feb. 18- 22, 2013, considerably lower
than the 64 ppb concentration cited
in the letter. In fact, that value was
the fourth highest eight-hour average ozone concentration in 2013 and
was recorded on May 2, 2013, during
the ozone season.
As shown in Figure 1 of the column, the indoor ozone concentrations fluctuated between 2 and 25
ppb when the corona discharge was
turned off and 25 to 40 ppb when
it was turned on. The observed
changes in indoor ozone were clearly
associated with operating the corona
discharge air cleaner.
The measurements were made in
an unoccupied classroom during the
school winter vacation, and the normal ventilation cycles were modified
to maintain uniform outdoor air
supply rates during the study. There
were no interferences from changes
in room or building occupancy, outside traffic patterns or from cleaning or maintenance activities in the
classroom during the study.
The study was designed to evaluate
changes in the indoor air quality of a
classroom while operating a corona
discharge air cleaner with a reduced

S E P T E M B E R 2 0 19

fresh air flow rate provided by the
ventilation system. The Department
found that the concentrations of
ozone, ultra-fine particles and aldehydes increased under these conditions. The study was not designed
to determine the health effects of
these air pollutants, but instead was
intended to test the claims that the
amount of fresh air brought into a
classroom can be reduced without
adverse impacts on air quality. Since
corona discharge air cleaners are
marketed as potentially beneficial to
health, it is appropriate to investigate those claims.

Todd Crawford, Patricia Fritz, Member ASHRAE,
and Thomas Wainman, New York State Department of
Health, Albany, N.Y.

Editor's Note: The authors' response
to a June 2019 letter regarding this column can be found at www.ashrae.org/
June2019Letters.

Improving the
Performance of
Steam Turbine
Chiller Plants
"Saving Energy: Improving the
Performance of Steam Turbine
Chiller Plants" by Charles G.
Copeland in August 2019 highlights
the importance of combined heat and
power-based steam power plants,
which could provide an economical
electrical energy source as well as
thermal energy for cooling/heating
for an overall efficient solution.
There are two factors which further need the author's attention and
comments:
1. Fuel Options. The advantages of
a steam system-based energy solution should be highlighted in terms


https://www.ashrae.org/june2019letters https://www.ashrae.org/june2019letters https://www.ashrae.org

ASHRAE Journal - September 2019

Table of Contents for the Digital Edition of ASHRAE Journal - September 2019

Contents
ASHRAE Journal - September 2019 - Intro
ASHRAE Journal - September 2019 - Cover1
ASHRAE Journal - September 2019 - Cover2
ASHRAE Journal - September 2019 - 1
ASHRAE Journal - September 2019 - Contents
ASHRAE Journal - September 2019 - 3
ASHRAE Journal - September 2019 - 4
ASHRAE Journal - September 2019 - 5
ASHRAE Journal - September 2019 - 6
ASHRAE Journal - September 2019 - 7
ASHRAE Journal - September 2019 - 8
ASHRAE Journal - September 2019 - 9
ASHRAE Journal - September 2019 - 10
ASHRAE Journal - September 2019 - 11
ASHRAE Journal - September 2019 - 12
ASHRAE Journal - September 2019 - 13
ASHRAE Journal - September 2019 - 14
ASHRAE Journal - September 2019 - 15
ASHRAE Journal - September 2019 - 16
ASHRAE Journal - September 2019 - 17
ASHRAE Journal - September 2019 - 18
ASHRAE Journal - September 2019 - 19
ASHRAE Journal - September 2019 - 20
ASHRAE Journal - September 2019 - 21
ASHRAE Journal - September 2019 - 22
ASHRAE Journal - September 2019 - 23
ASHRAE Journal - September 2019 - 24
ASHRAE Journal - September 2019 - 25
ASHRAE Journal - September 2019 - 26
ASHRAE Journal - September 2019 - 27
ASHRAE Journal - September 2019 - 28
ASHRAE Journal - September 2019 - 29
ASHRAE Journal - September 2019 - 30
ASHRAE Journal - September 2019 - 31
ASHRAE Journal - September 2019 - 32
ASHRAE Journal - September 2019 - 33
ASHRAE Journal - September 2019 - 34
ASHRAE Journal - September 2019 - 35
ASHRAE Journal - September 2019 - 36
ASHRAE Journal - September 2019 - 37
ASHRAE Journal - September 2019 - 38
ASHRAE Journal - September 2019 - 39
ASHRAE Journal - September 2019 - 40
ASHRAE Journal - September 2019 - 41
ASHRAE Journal - September 2019 - 42
ASHRAE Journal - September 2019 - 43
ASHRAE Journal - September 2019 - 44
ASHRAE Journal - September 2019 - 45
ASHRAE Journal - September 2019 - 46
ASHRAE Journal - September 2019 - 47
ASHRAE Journal - September 2019 - 48
ASHRAE Journal - September 2019 - 49
ASHRAE Journal - September 2019 - 50
ASHRAE Journal - September 2019 - 51
ASHRAE Journal - September 2019 - 52
ASHRAE Journal - September 2019 - 53
ASHRAE Journal - September 2019 - 54
ASHRAE Journal - September 2019 - 55
ASHRAE Journal - September 2019 - 56
ASHRAE Journal - September 2019 - 57
ASHRAE Journal - September 2019 - 58
ASHRAE Journal - September 2019 - 59
ASHRAE Journal - September 2019 - 60
ASHRAE Journal - September 2019 - 61
ASHRAE Journal - September 2019 - 62
ASHRAE Journal - September 2019 - 63
ASHRAE Journal - September 2019 - 64
ASHRAE Journal - September 2019 - 65
ASHRAE Journal - September 2019 - 66
ASHRAE Journal - September 2019 - 67
ASHRAE Journal - September 2019 - 68
ASHRAE Journal - September 2019 - 69
ASHRAE Journal - September 2019 - 70
ASHRAE Journal - September 2019 - 71
ASHRAE Journal - September 2019 - 72
ASHRAE Journal - September 2019 - 73
ASHRAE Journal - September 2019 - 74
ASHRAE Journal - September 2019 - 75
ASHRAE Journal - September 2019 - 76
ASHRAE Journal - September 2019 - 77
ASHRAE Journal - September 2019 - 78
ASHRAE Journal - September 2019 - 79
ASHRAE Journal - September 2019 - 80
ASHRAE Journal - September 2019 - 81
ASHRAE Journal - September 2019 - 82
ASHRAE Journal - September 2019 - 83
ASHRAE Journal - September 2019 - 84
ASHRAE Journal - September 2019 - 85
ASHRAE Journal - September 2019 - 86
ASHRAE Journal - September 2019 - 87
ASHRAE Journal - September 2019 - 88
ASHRAE Journal - September 2019 - Cover3
ASHRAE Journal - September 2019 - Cover4
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