Environmental Engineering Reference
In-Depth Information
.
4..
Barriers that separate the person from the unwanted energy by time or space:
The. primary. purpose. is. to. prevent. the. unwanted. energy. from. contacting.
the.person.
Generally,.barriers.in.1.provide.more.positive.protection.than.those.in.2,.and.2.more.
than.3,.etc.
Some.of.the.barriers.are.not.clear-cut..Barriers.on.the.person.could.very.easily.
prevent.the.unwanted.energy.from.contacting.the.person..Sometimes.they.serve.to.
reduce.the.potential.injury..For.example,.goggles.will.keep.objects.out.of.a.person's.
eyes..But.if.the.object.has.any.force.behind.it,.it.could.break.the.goggles..However,.
the.amount.of.damage.to.the.eye.should.be.less.as.a.result.of.the.amount.of.impact.
the.goggles.have.absorbed.
Barriers.on.the.person.can.also.be.distinguished.from.barriers.between.the.person.
and.the.energy.source,.if.the.former.is.considered.as.being.extensions.of.the.person..
Gloves.are.extensions.of.the.hands.and.skin;.goggles.are.extensions.of.the.eyes..This.
is.in.contrast.to.a.guard.or.fence,.neither.of.which.is.an.extension.of.the.person,.but.
they.do.protect.more.parts.of.the.body.than.personal.protective.devices..Any.per-
sonal.protective.equipment.is.a.barrier.on.the.person..A.more.dificult.discrimination.
exists.between.barriers.that.separate.the.person.from.the.energy.source,.and.barriers.
that.separate.the.person.from.the.energy.by.time.or.space..The.latter.is,.in.fact,.a.
special.case.of.the.former..When.we.think.of.barriers.between.the.person.and.energy.
source,.we.think.of.barriers.that.are.constructed.of.some.substance.engineered.for.
the.purpose.of.separating.the.person.and.the.energy.source.
Time. and. distance. are. always. available. and. become. a. barrier,. often. based. on.
someone's.judgment..Because.time.and.space.are.easy.to.make.into.barriers,.there.
needs.to.be.clariication.of.time.or.space.barriers..A.time.or.space.barrier.should.be.
based.on.a.written.policy.or.regulation,.or.must.signal.that.the.time.or.space.barrier.
is.in.effect..This.criterion.limits.the.person's.judgment..The.signal.or.policy.tells.the.
person.what.the.safest.waiting.period.or.distance.is.
PhysIcAl BArrIer AnAlysIs
Physical.Barrier.Analysis.(PBA).is.based.on.four.assumptions:
.
1.. There.are.four.types.of.physical.barriers..When.a.physical.intervention.can.
prevent.an.accident,.that.intervention.will.always.be.one,.or.a.combination,.
of.the.four.types.of.physical.barriers.
.
2.. Accidents.not.caused.by.the.lack.of.a.physical.barrier.cannot.be.prevented.
by.introducing.such.a.barrier.
.
3.. Being.able.to.identify.accidents.that.a.physical.barrier.could.have.prevented.
and.those.that.a.physical.barrier.could.not.have.prevented.allows.the.analyst.
to.it.remedies.to.the.causes.of.accidents.more.accurately.
.
4.. Accidents. related. to. physical. barriers. are. almost. always. the. easiest. type. to.
prevent.
