The Wallace miner. [volume] (Wallace, Idaho) 1907-current, 1922-01-05

u lut CAlltA NaUSt VI lllllltlh CONSUMPTION
but it is now recognized that Their
may be other factors OF almost equa
influence. such as high temperature
and humidities. harmful gases and lac
of ar movement all of which may b
modified by ventilation 1t appear
that. with a dry-bulb temperature be
low as f.. mine working places ma!
be comparatively comfortable, ire
spective of movement Of air or humid
ity. However, the presence of impure
air may produce uncomfortable or un-
safe conditions; such places may be
both uncomfortable and unhealthful il
large quantities OF finely divided dust
are present. With a dry-bulb air tenn
perature Of above 750F., comfort and
maximum working efficiency can be
attained only when air is moving, this
being especially true if the air has a
high humidity, The exact velocity
necessary Is variable, dependent upon
the temperature and the humidity.
Saturated atmospheres. up to nearly
blood temperature. may be made en-
durable and even comfortable by pro-
viding sufficient velocity. The still air
in metal mines at about S. +. and 80
to 1909 humidity has little effect on
persons at rest but with those doing
even moderate work the body tempera-
ture rose to over 1OO'F.. the blood
pressure fell perceptibly and the pulse
beat rose. In still air, with tempera-
lures of go to 1OO0F. and about 1897
humidity. even when almost at rest the
body temperature rose quickly. reach
ing over 102 F.. the blood pressure fell
rapidly. the pulse-beat increased alb
normally and was sensitive to even
slight exercise; perspiration was pro-
fuse; dizziness, physical weakness
mental sluggishness and headache
were common; upon attempting even
slight work these symptoms were
greatly augmented.
Humidity, even up to the saturation
point does not appear to be harmful
to health, comfort OF efficiency until
the temperature is above 20 f.; If stiff
ficient movement be supplied high
humidity is not harmful until the tenn
perature is over 9OoF. Except in blind
working places the air is not particu
larly deficient in quality However
the air of drifts crOsscuts raises,
wines and Slopes is likely to be def
cient in oxygen or high in nitrogen or
carbon dioxide, and possibly in carbon
monoxide oxide or nitrogen or other
of
in metal mines.
Almost all explosives used in metal
mines give off small percentages of
poisonous fumes; when these fumes !
are not removed from working places |
by ventilation they cause headache, |
nausea, and possibly death The gela-
tin dynamite gives off less dangerous |
gases than do the ammonia dynamites;
the latter give off less than the |
5 traig h nitro-glycerin dynamites |
Hence the straight nitro glycerin dyn-
antics should not be used under |
ground and all places using explo-
sives should be thoroughly ventilated
after blasting and before the workers
again arrive Good ventilating cur
rents should also be provided while
the ore is being shoveed. Compressed
air is not effective in removing explo-
sive fumes. Comparatively small
quantities of impurities in stagnant air
causes headache. and this is particu
larly true when the temperature is
over 8OoF. However, these are not no
ticeable when there is perceptible
movement of the air
Frequently in blind and working
faces in metal mines the air is so low
in oxygen that a candle will not burn,
and carbide lamps must be used; the !
oxygen content is below 1870. Occa- |
sionally entire mines are found in this |
condition and many metal mine mana
gers contend that it is satisfactory.
There is no question that men working
in an atmosphere that will not sup
port the combustion of a candle can
not operate efficiently; their health
must suffer ultimately. Mines with
cool working places are likely to be
extremely dangerous unless provision
De made to remove explosive fumes
luQ line QubL ny Ntnllldlln6 Gull tiANos
The efficiency of workers in mines
n which the temperature is high
above 75'F.) are likely to decrease
rom $50 TO 7595. Workers are likely
o become sick unless moving currents d;
# air are supplied. The outcome is
fastened and intensified if fine dust be
present, especially siliciOus dust, and {
( there be much blasting done, espe- {
tally when men are in the mine Many {
ccidents in metal mines are due to {
ventilation. The failure to :
emove smoke and fumes prevents the
roper inspection of working places. q
borrower, men are likely to be affect !
d by dizziness or by lack of ability to {
hink clearly or quickly, or they may {
amt at an inopportune time and be
illed. Men have been known to drop i
cad from heart failure in these hot {
laces. {
Variations in surface-air tempera- I
ure and humidity change conditions }
tile If at all at the faces in those Z