Rock Island Argus. (Rock Island, Ill.) 1893-1920, 1914-11-10
VENTILATION.

At this time OF year when the tend
ency for nearly everybody is to shrink
away from the first drafts OF winter
and to close up homes, offices and pub
lie conveyances till the exclusion of
fresh air amounts to a menace to the
public health a discussion of ventila-
ton from scientific standpoint is of
interest and timely.
In the light of more modern studies
in ventilation the Journal of the Amer
lean Medical association says it would
seem that the real explanation of the
i'll effects of bad ventilation is not to
be found in the chemical composition
of the atmosphere breathed. One is
constrained to ask wherein the dis
agreeable or detrimental influences of
poorly ventilated spaces lie. The var
ious phases of this vital and timely.
though not new subject were dis
cussed some time ago by qualified eX-
perts in a symposium on ventilation at
the Chemists club in New York city.
There is unanimity among them re-
garding the possible significance of
the chemical vitiation of the air. Pure
air contains nearly u per cent of oxy-
gen This may be reduced to Il per
cent, a proportion too small even to
support ordinary combustion, before
its diminution becomes harmful. Ex-
cept in extreme conditions the amount
of oxygen in the closest halls crowded
with people practically never falls be-
low 20 per cent Oxygen will. there
fore, take care of itself and may prob
ably be wholly left out of considera-
ton in ventilating systems. Indeed,
Henderson has reminded us that il is
necessary to 20 only short distance
up into the mountains to come under
an atmospheric pressure. such as to
reduce the oxygen supply much more
than il is reduced in crowded assem-
blies, and yet mountain air is especial
y healthful. The amount of oxygen in
the air apparently has little or moth
ing TO do with the stimulating or de
pressing properties of the atmosphere
breathed in ordinary life.
The air, under the usual conditions. /
contains about 4 parts of carbon di-
oXid per ten thousand parts O.O4 per
cent? and the standard" of desired 1
purity for the air of dwellings was /
long placed as low as parts per ten /
thousand. Experimentation indicates |
however, that il does not become /
harmful to man until the carbon di-
OXid accumulates to above / per cent
or nearly forty times its usual amount
The air in crowded rooms very rarely
reaches o. per cent, so that evidently
a quantity of carbon dioxid far ex-
ceeding the highest hygienic limit
which has hitherto been set up as a
standard" can be breathed with i'm
punity
The long-debated idea that expired
air contains organic matter which is
toxic has been abandoned by most
The bacteria in the
air need not be considered. since the
uinmportance of the air
as vehicle Of infection is recognized
We may conclude with reasonable Ger
-ainty that the discomfort in badly
ventilated place is due to the physical
condition of the air in respect to tenn
Derature. humidity and movement,
and not to any chemical properties
The symptoms noted in closed crowd
ID rooms-restlessness headache. dir
:iness, nausea, etc.-are to be attri-
Juted to heat retention. Overhedting
s the chief evil 10 be guarded tgainst
II ventilation at present. The chief
i5nger of our torrid summer days is
rot the heat alone. but the combined
leat ard humidity; it - the same fac {
ors which are responsible for the evil
fleets of the confined air OF rooms. I
There j. no doubt that ;hc air of cur !
American living-roms and many
choOl rooms and other assembly
chambers is kept too warm.
Further investigation OF tie condi- s
ions actually existing in the midst Of {
what is assumed to be Inadequate
-entilation are called for The extra 7
thing about the shifting prac- a
ices in the ventilation of public build I
ngs is that sweeping conclusion and L
ar-reaching changes in policy have h
cen arrived at without any detailed t
= systematic study such as seems es- {
entail in order TO establish a safe
asis for action. I