Evening star., 1935-11-10
Odd Blazes Are Studied
i At "Explosion Factory
Freak Blasts of Peculiarly Destructive Nature
Traced to By-Product Gas of Aluminium
and Extinguishing Liquid.
By Randolph Roberts.
4 N ENORMOUS fire RACES in ar

~ acteristic speed, flremen ap-
4 a pear on the scene, Within an
hour they seem to have the situation
fairly we'll under control, when, all
at once, for some mysterious reason
there is a terrific explosion, and then
another and another. Walls are
blasted from their moorings Two fire.
men fall into the debris. Thousands
OF dollars worth of materials and
other property have been destroyed.
Another American tragedy has taken
place.
A Federal specialist is called upon
for advice. After a weeks research he
makes a peculiar announcement. 1t
seems that the explosions actually
were caused by the constant play OF
streams of water on the blaze. In
other words. a violent chemical reac-
ton has taken place between the
water and a large amount OF hot
aluminium powder that was present in
large amounts in the factory. The
oxygen from the water has united
with the aluminium, causing it to burn
more rapidly, while the hydrogen,
which is an explosive gas, is liberated.
Fires caused by water! Ironically
enough, the very liquid that frSt
comes to mind as the chief means OF
stopping large-scale conhagrations has
been the cause. directly or indirectly,
OF so many fires in factory and farm
in recent months that Federal re-
search experts armed with unique test
apparatus, have launched an investi-
cation.
In charge of the novel program is
Dr.. David J. Price of the Bureau OF
Chemistry and Soils, United States
Department of Agriculture. Most OF
his tests are being conducted in an
especially devised experimental barn
at Beltsville, Md, and also at the
bureaus explosion factory" at Ar
lington Farm, Va.
DR. PRICE points out. first Of all,
that since so many fires caused
by water are connected with dust ex-
plosions, much of his bureaus re-
search work is being conducted with a
view to determining the precise chem
ical relations between water and vari-
Gus kinds of dust. He explains, THE
major Federal aim is to save billions
of dollars worth of property and ma
terials from the dynamite Of dust"
There are at least $4,000 industrial
plants in this country subject to the
dangers of dust blasts. These plants,
normally employing more than mil
lion workers. manufacture products OF
an annual value in excess of 100000
600. Among the various products
which yield explosive dusts are grain,
starch, wood. paper. cork, fertilizer
dried milk, chocolate. rubber and sui
phur.
AS striking example of the dam
age a great dust explosion can &C.
complish, take an instance of few
years ago, when what is believed to
have been the largest dust fire in his
tory occurred in the Chicago & North
western grain elevator. South Chicago,
at that time the worlds largest eleva-
tor, of 100000 bushels capacity.
The property damage in this one
plant exceeded $4,000 900. All the men
in the building at the time-six, all
told-were killed. Records of no less
than $50 explosions of this character
have been obtained by the Federal in
vestigators. In 1874 of these disaS-
ters 434 persons were killed and 866
were injured In 449 cases the prop
erty loss amounted to approximately
$46,000,O00
OF course, these explosions aren't
all caused directly or indirectly by
the chemical reaction between water
and dust. However. here's an all too
common situation Mr.. Price says: An
ordinary fire takes place in a large
grain elevator from common causes,
such as friction of a rubbing rope on
a pulley, or else the constant contact
between a broken metal bucket and
an elevator belt. Firemen are sum-
moned. According to their usual pro-
cedure, they turn large amounts OF
water on the blaze, an explosion oc-
ours, one or two fire fighters are killed
what has happened.
Here's what takes place, Mr.. Price
says: The full stream of water has
struck settled dust in various parts
of the building. The water forces the
dust cloud onto the fire, causing the
explosion. AS a precautionary meas
ure, Uncle Sans experts advise fire.
men never to turn on the full pressure
of tfe water when fighting a dust fire,
but instead to use spray, and in such
careful fashion that it will not make
the dust rise into a cloud.
"EXPLOsI0Ns made to order" has
been the slogan Of the Federal
scientists while testing their new "ex-
piosion factory at Arlington. Va,
which Is equipped with swinging iron
doors and windows to permit the force
t,f blasts to escape into the outside air
without blowing up the test buildings
The novel factory" consisting Of a
room, gallery am. tower, produces
explosions by blowing starch, flour
grain dust or other powdered COM
bustible material from a number OF
hemispherical cups or containers. The
dust cloud is ignited by blowing II
onto a heated electric coil.
Probably the most novel feature o1
the tests lies in tn fact that the dem
onstrators can cause seprate explo'
sions in the room, the gallery, the
tower and sometimes in all parts Of
the model building at once. The glass
windows can be blown out or protected
as desired, by simply controlling the
size of the vents (openings for the re-
lease of pressure), the main purpose
of the studies being to show the pos.
sibility of releasing dust explosion,
through properly proportioned vents
without doing structural damage.
Thus far there have been hundreds
Of tests conducted by DR.. Price and
his engineer associates, Hylton j
Brown and r. ard l.. Hanson. In
which almost every conceivable type
of dust was used. These tests proved