Evening star. [volume] (Washington, D.C.) 1854-1972, 1938-08-08
HEL|UM ENABLES
D|VERST0REACH
RECORD DEPTHS
The Gas Is Substituted for
Nitrogen in Breathing
Mixture in D.. c. Tests.
SCOTT. DESCENT MADE;
DECOMPRESSION QUICK
Sea Conditions Simulated in Tank.
4O0.Foot Level Reached in
Open Water.

Use of helium and oxygen as a syn
thetic breathing mixture has en-
abled divers at the Washington Navy
Yard to reach record depths, the
Navy Department disclosed today.
BY breathing this mixture. instead
of compressed air. Master Divers Will
liam Badders and j. H. Mcdonald re-
Gently reached depths of 500 feet
under simulated sea conditions in the
diving tank. Actual conditions were
simulated by partially filling the tank
with water and applying air pressure
equivalent to sea pressure at 500 feet.
Subsequently. open-sea tests were
made on the submarine rescue vessel
U. S. S. Falcon, during which an &C.
tual depth of more than 400 feet was
reached by Master Diver Badders.
whose home is in Annapolis. Md. Diver
Mcdonald is from Las Animas, Colo.
In the past the depth to which
divers could descend and the length
Of time they could stay at such depths
we're governed by the physiological eff
fects of the constituents of the COM
pressed air supplied to meet their
respiratory requirements. Fifteen
minutes was the length of time divers
could stay at depth of 800 feet and
a decomposition time of four to fve
hours was required.
Continuous operations at great
depths. therefore, required a large
number OF divers and was Of necessity
slow. BY decreasing the oxygen con-
tent and increasing the nitrogen con-
tent Of the mixture used, greater
depths were made possible. it was
found. but use Of more nitrogen neces-
STATED longer decomposition period.
Standard Suits Used.
Both the divers at the Navy Yard
here used standard rubber diving suits
of the type used in attempting the
rescue Of trapped submarine crews. A
depth of 306 feet had been reached
previously in attempts to salvage an
undesea craft of Honolulu. Last year
a descent of 420 feet was credited to
Max E. Nohl. commercial diver who
used the oxy-helium mixture at Mil
waukee. but experts here said he used
q different type OF equipment.
Far greater depths have been reached
by such devices as DR.. William Beebe's
bathysphere, but these permit only
observation.
In preliminary experiment with
the oxygen-heliu mixture a decom-
preston period Of only Is minutes was
needed after a dive" under pressures
equal to $50 feet was made.
Needed for Submarines.
In an official announcement the
Navy Department said, with subma-
rines being constructed to operate at
ever-increasing depths, the possibility
of the sinking of such vessels in great
depths emphasized the necessity for
devising means whereby outside
assistance can be rendered by divers.
Investigation Of the use Of helium
was started IS years ago at the sug-
gestion of the Bureau of Mines. Early
experiments, chiefly on animals, were
carried on at the Bureau of Mines
Experimental Sation in Pittsburgh. In
1927 the experimentation was moved
to the Washington Navy Yard.
In all the hundreds of tests made by
the Navy there has been no evidence
OF harmful effects from breathing
oxy-helium mixtures. In fact, the
diver using this mixture retains a
clarity Of mind heretofore unknown.
Helium, the rare non-inflammable
gas of which the United States is be-
lieved to have a virtual monopoly, is
inert and is absorbed by blood and
tissues much less than nitrogen,
when it replaces in the synthetic
mixture.
Experts found that the mixture had
peculiar chilling effect under high
pressures. To Offset it, the divers
wore electrically-heated underwear
under the standard diving dress.