Environmental Engineering Reference
In-Depth Information
deeper.muscles,.resulting.in.reduced.muscular.strength.and.stiffened.joints..Mental.
alertness.is.reduced.due.to.cold-related.discomfort..For.all.these.reasons,.accidents.
are.more.likely.to.occur.in.very.cold.working.conditions.
The. main. cold. injuries. are. frostnip,. frostbite,. immersion. foot,. and. trenchfoot,.
which. occur. in. localized. areas. of. the. body..
Frostnip
. is. the. mildest. form. of. cold.
injury..It.occurs.when.ear.lobes,.noses,.cheeks,.ingers,.or.toes.are.exposed.to.cold..
The.skin.of.the.affected.area.turns.white..Frostnip.can.be.prevented.by.warm.clothing.
and.is.treated.by.simple.rewarming.
Frostbite
.is.a.common.injury.caused.by.exposure.to.extreme.cold.or.contact.with.
extremely.cold.objects..It.occurs.when.the.tissue.temperature.falls.below.the.freezing.
point..Blood.vessels.may.be.severely.and.irreparably.damaged,.and.blood.circulation.
may.stop.in.the.affected.tissue..In.mild.cases,.the.symptoms.include.inlammation.of.
the.skin.in.patches,.accompanied.by.slight.pain..In.severe.cases,.there.could.be.tissue.
damage.without.pain,.or.there.could.be.burning.or.prickling.sensations.resulting.in.
blisters.. Frostbitten. skin. is. highly. susceptible. to. infection,. and. therefore. gangrene.
is. possible.. In. cases. of. suspected. frostbite,. the. body. should. be. slowly. warmed. to.
normal.temperature..Frostbitten.limbs.should.be.warmed.irst.in.cold.water.at.50°F.
to. 60°F.. The. water. temperature. should. increase. by. 10°F. every. ive. minutes. to. a.
maximum.of.104°F..Complete.recovery.takes.several.days..Residual.effects.such.as.
cold.feet,.numbness,.abnormal.skin.color,.and.pain.in.joints.may.continue.for.several.
days,.especially.in.winter.
Immersion foot
.occurs.in.individuals.whose.feet.have.been.wet,.but.not.freezing.
cold,.for.days.or.weeks..The.primary.injury.is.to.nerve.and.muscle.tissue..Symptoms.
are. numbness,. swelling,. or. even. supericial. gangrene.. Trenchfoot. is. “wet. cold.
.disease”.resulting.from.exposure.to.moisture.at.or.near.the.freezing.point.for.one.to.
several.days..Symptoms.are.similar.to.immersion.foot.(swelling.and.tissue.damage).
Hypothermia.can.occur.in.moderately.cold.environments;.the.body's.core.tem-
perature.does.not.usually.fall.more.than.2°F.to.3°F.below.the.normal.98.6°F.because.
of.the.body's.ability.to.adapt..However,.in.intense.cold.without.adequate.clothing,.
the.body.is.unable.to.compensate.for.the.heat.loss,.and.the.body's.core.temperature.
starts.to.fall..The.sensation.of.cold,.followed.by.pain,.in.exposed.parts.of.the.body.
is.the.irst.sign.of.cold.stress..The.most.dangerous.situation.occurs.when.the.body.
is.immersed.in.cold.water..As.the.cold.worsens.or.the.exposure.time.increases,.the.
feeling.of.cold.and.pain.starts.to.diminish.because.of.increasing.numbness.(loss.of.
.sensation)..If.no.pain.can.be.felt,.serious.injury.can.occur.without.the.victim.noticing..
Next,.muscular.weakness.and.drowsiness.are.experienced..This.condition.is.called.
hypothermia
.and.usually.occurs.when.body.temperature.falls.below.92°F..Additional.
symptoms.of.hypothermia.include.interruption.of.shivering,.diminished.conscious-
ness,. and. dilated. pupils.. When. body. temperature. reaches. 80°F,. coma. (.profound.
unconsciousness).sets.in..Heart.activity.stops.around.60°F.and.the.brain.stops.func-
tioning.around.63°F..The.hypothermia.victim.should.be.immediately.warmed,.either.
by.being.moved.to.a.warm.room.or.by.the.use.of.blankets..Rewarming.in.water.at.
104°F.to.108°F.has.been.recommended.in.cases.where.hypothermia.occurs.after.the.
body.was.immersed.in.cold.water.
