The New York herald., 1921-09-10
Indoor and Outdoor Air.
Ozone as Factor in Human Health
and Comfort.

| jacques W. Red,cdD IN the Medical Times.
Whether or not the presence of ozone
Is factor in the air which concerns
human comfort and health is a matter
yet to be learned. The bracing quail
ties that come with the northwest wind
of a cold wave are not due to any ex-
Of ozone in the air Of a northwest cold
wave. the air Of greatest health giving.
Is very small. Moreover. there Is nei-
ther more nor less ozone In the air OF
a refreshing June morning than in the
air of sultry August afternoon.
The determination of comparative
ozone content Of indoor and out of door
air is necessary to form a conclusion Of
the effect of ozone. Quantitative deter
limitations Of ozone are not easily made !;
qualitative tests are easily made and
elaborate apparatus is not required. A
solution having the proportion Of four
grains Of potassium iodide and twenty
FIVE grains Of starch to the fluid ounce
Of water is recommended. In preparing
the solution one would better dissolve
the potassium iodide In the minimum
amount of water and boil the starch In
the remaining water. The two solutions
when mixed may be strained through
muslin II necessary the mixture Is fl
tered with difficulty.
1t Is most conveniently kept in shall
low. wide mouthed jar. which should
he closely stoppered. Slips OF unsized
paper dipped into the solution may be
pressed between folds Of old muslin
cloth or hung In the air saturated ex-
posure varying from three to ten hours
Is required. Ozone decomposes the po-
tassIum iodide. turning the test paper
blue. The sensitized slips of paper
should be exposed. one in living room,
the other on covered porch or in a
thermometer shelter. The depth of blue
in each case win enable one to deter
mine roughly the difference in the pro-
| portion OF ozone indoors and out OF
doors. The oxides of nitrogen almost
always present in the air will also re-
duce potassium iodide Inasmuch as
! they act merely as oxidizers their ac-
tion on organic matter does not differ
from that of ozone.
| So far as living rooms are concerned
tne cOnultiOnS III living rooms uurnlS
winter are practically those OF the sum-
mer hot spell. Nowhere out of doors Is
the air so still as in ordinary living
rooms when the winter heating plant is
in operation. and nowhere out of doors
Is the air so dirty. The result is meas
+, urcd in terms Of human life. In most
of the large cities OF the northern
United States the January death rate is
about so per cent. greater than that Of
| June.
| From time to time the interesting
question Is propounded Does sunlit air
| possess a radioactive or a vltalizing
property which Is lost when the air is
forced through long metal ducts after
It has been In contact with the heating
! coils of a mechanical ventilation plant?
Up to the present time evidence that
out of door air possesses such a prop
erty Is wanting nothing to support such
theory has been discovered. Deep
spring waters frequently are radioactive
when fresh. They lose the property
after they have been bottled. And IL
sunlit air possesses any such property
II may be safely assumed that the treat
mcnt of artificial warming and circula-
ton is sufficient to destroy 1t.