The sun. [volume] (New York [N.Y.]) 1833-1916, 1915-03-19
SUBWAY VENTILATION.
A Plan TO Rid the Town OF the AbOm-
Unable Sidewalk Gratings.

IuHUit NIueWuIh vThtIUks.
To THE EDITOR OF THE SuN-Sir. TIL,
proposed use of extended ide wall
gratings opening out of the new sys
TEN OF subways has been properly me
with the repeated protests of adjoln
ing property owners.
There is little question about its beinl
a nuisance. and it has little to offel
in the a Of compensation as a meal
of subway ventilation.
Ii seems astonishing that the lesson.
taught by the unqualified failure II
the attempted ventilation of the pres
ent subways. which are using such
gratings. should not bring home a
proper appreciation OF the elementary
principles OF ventilation.
The fallacies advanced by those who
described the means provided to secure
the needed ventilation in our present
system OF subways were so apparen,
to me that | was led to call attention
to them at the 1905 annual meeting
of the American Society of Heating and
Ventilatlng Engineers.
This was six months before our pres
ent operating subways were opened and
at that meeting ! predicted that those
using the subways would suffer. espe.
cially in the summer. My statements
were quoted on the following day tJan-
uary is, 1906 by THE Sun.
In the Engineering NeWs Of August
s. 1901. | described a system of sub.
way ventilation which, with proper
notifications. could he applied to our
new system of subways and there IL
no question hut that it would give the
looked for ssults.
The article received very favorable
editorial and other comments. II dealt
with d much more difficult problem In
NapfgIaftOp fhan .xfete in TIM MAUI aNgtefn
of %subvsys, az II provided for the VEN
t~ilation OF the old Park avenue tunnel
where coal burning locomotives were
used will trains running OUT of the old
Grand Central Depot. A change to cleo
trio locomotives afterward made this
installation unnecessary.
II such an installation had been In
use In our present subway In the early
part OF January the dense pungent
smoke from the burning insulation
would have been 30 rapidly remove
that those in the rains would have
experienced little inconvenience.
At the above mentioned meeting OF
the Heating and N%entilating Engineers
| stated that IL was impossible to use
moving trains as pistons for the pur-
pose OF positively forcing foul air ahead
of them and drawing In fresh air behind
them. unless the train fitted into the
SDdtt pTpNlutu lpI IL Will SOluf ufEItt
Of c~loseness. Further. II was necessary
to ave this trainway passage sealed
with approximate tightness 20 as 70
nave no inlets or outlets excepting at
definite separated positions. some dis
lance apart. where the vitiated air
forced ahead of the train could escape
and the fresh air. drawn in behind the
train, could enter.
This condition exists. approximately.
- tlA IIftIuDn f,haS hut IL Attr nrnaTpF
subways the open chamber in which the
train operates in both directions. a
churning up OF the air occurs without
positively forcing this air either In or
out of the subway. and with these
bodies M air contained in the open
subway hurled about by the moving
trains without definite direction this
condition makes nearly any system of
ventilation or positive air displacement
almoe impossible.
Should each train p~assageway he
parttioned off. as has been proposed
and the long grated sidewalk opening
run continuously along the sides OF these
~passageways. such an arrangement Will
simply defeat the perfect pistonlike ac-
ton Of the train, depended upon for
ventilation. which requires considerable
compression and a positive movement
81 air In front ~ the train in the same
Ilrtctlpn the tram II trdNtllllk. = very
slight Improvement Owe the present
conditions Of subway suffering will re-
suit from the use of such arrange
mcnt.
As I understand ". Mr.. Clark. whose
plans have been submitted. proposes 10
run air ducts over the top OF the sub
way passages, these ducts. or pipes. 10
have a series Of openings into the en-
closed subway. and to carry these pipes
continuously along the top OF the sub
way 10 distant orifces which open into
the outside air.
BY the use OF fans. TO keep the air
moving In a positive direction In these
pipes toward the mex street opening.
] understand that he expects 20 empty
the subway passage Of Its vitiated air
and Introduce a sufficient quantity OF
fresh outside air. At the several stree,
openings OF this air duct he proposes TO
erect kiOsks
Mr.. Clark's idea TO enclose completely
tho subway passages II have open
ings at distant intervals is working
in the right direction. but when We
consider how small the cross sectional
area Of the air pipes must be as COM
nared with the cross sectional area of
the subway passage itself We can SEQ
that the fans will have 10 move the
air through these pipes Al a very high
velocity to handle the quantity OF ar
required TO secure the necessary ven-
~tilation. Such high ve.ocities in NOV
ing air require a large expenditure of
power 10 operate the fans, and II
strikes me that the system would fun
ther require a l,rcc number ~ con-
paratively small sized fans 10 operate
II successfully
Following the general design offered
In the EnGtreeriHo NcWS article referred
to. ! would prefer to design proper
closures between the trainUay passages
and use large fans AZ tho stations, taxi
ing in fresh air midway botNeeu them
Al other ououings. including sidewalk
rratiugs. must nc closed To secure eff
cieut results. hut this does not preclude
the provision of the proper number ~
emergency exits,
This ~ "A straight engineering p-opo-
sit,on. capable OF successful solution :
and although the strongest argument
dgainsi II IL the cost of such an equip
meut, II resolves itself into = question
As 20 whether such cost should stand
in tho way Of securing a comfortabl"
and hcalthful subway ur not,
No other system that will be equally
efficient would cost loss than this ue
ALBERT y. CARY.
NEW YORK. March II.