The Marietta journal. (Marietta, Ga.) 1918-1944, 1920-08-06
IN.
METAL MINES

quate ventilation of metal mines than
of coal mines. The latter require afr
currents to remove explosive gases
and the fumes of explosives, but metal
mines, In addition to the need Of re-
moving fumes of explosives and occa-
sionally explosive gases, frequently
have need of removing dusts danger
Gus to health, reduction of high tenn
peratures and high humidity, and re-
moval of inert, but unhealthful gases"
The main features affecting metal
mine ventilation as outlined in part
by Mr.. Harrington. are:
Movement of Air-This involves eff
fects of air movement at various tenn
peratures, humidities, and with GER
tain gases present, and the advisable
velocity of current to use.
Temperature-The temperature of
the air in q metal mine is influenced
by the outside air temperature, under
ground rock and water temperature,
oxidation of ores and timbers, mine
fires, friction of air due to velocity Of
flow, movement of ground, firing of
shots, quantity of air circulating, heat
from breathing of men and animals,
heated air from other mines, heat from
electric motors and other machinery.
Humidity-The humidity of mine air
depends on the relative humidity of
surface air, wetness of shafts and
workings, the velocities, quantities,
and temperatures of the air circulated.
Where small fan units are employed
to force air through galvanized iron
humidity through absorption or depo-
sition of moisture.
Mine gases and dusts-The intake
air is usually pure, except in rare in
stances where smoke or dust from sur
face works may be present. The air
in the mine changes through breathing
of men and animals, burning of lights,
oxidation of ore or timber, gases issu-
ing from strata, gases from mine fires,
fumes from explosives, gases from
compressed air, gases from operation
Of machinery, dusts from drilling,
DioOllHS, CilllS OtlISl NOlhs
Studied by Experts.
The writer says that the bureau of
mines and the, United States public
health service, in conjunction with the
investigation of mine dusts and gases,
are studying effects of temperature
and humidity on workmen's health and
efficiency.
Few mines having humid hot work.
ing places with no circulation have es-
capped without one or more fatalities
from heart failure which is really
heat prostration," says the writer, yet
proper air circulation would make
these mines endurable.
"In some mines where gases such as
nitrogen or carbon dioxide issue from
the strata, fatalities and many cases
of gassing have occurred from made
quate ventilation; the remedy is force
or pressure ventilation with constant
vigilance. Many lives have been lost
as well as much property, from fires
in metal mines because no ventilating
equipment arranged to control the air
currents in such an emergency had
been provided.
Miners consumption probably kills
ut least. 1000 metal miners annually
in the United States, and causes loss
of time aggregating millions Of dol
lars the misery and suffering to min
ers and their families cannot be esti-
mated. Yet the causes of this disease
could be reduced rs per cent, if not
wholly eliminated by proper preventive
measures on the part of operator and
miner, one of the most potent meas
ures, as previously mentioned. Is ade 4
anate yspfilatiQk 2