Environmental Engineering Reference
In-Depth Information
1¼" Safety zone
FIgure 24.5
Head.protection.suspension.clearance..(Courtesy.of.the.United.States.Depart-
ment.of.Energy.)
heAd ProtectIon
Employers. must. provide. head. protection. for. employees. if. objects. might. fall. from.
above. and. strike. them. on. the. head,. if. they. might. bump. their. heads. against. ixed.
objects.such.as.exposed.pipes.or.beams,.or.if.they.work.near.exposed.electrical.con-
ductors..In.general,.protective.helmets,.or.hard.hats,.should
•.
Resist.penetration.by.objects.
•.
Absorb.the.shock.of.a.blow.
•.
Be.water.resistant.and.slow.burning.
•.
Come. with. instructions. explaining. proper. adjustment. and. replacement. of.
the.suspension.and.headband.
Hard. hats. require. a. hard. outer. shell. and. a. shock-absorbing. lining.. The. lining.
should.incorporate.a.headband.and.straps.that.suspend.the.shell.from.1.to.1
1
/
4
inches.
(2.54.to.3.18.centimeters).away.from.the.user's.head.(see.Figure 24.5)..This.design.
provides. shock. absorption. during. impact. and. ventilation. during. wear.. As. with.
devices.designed.to.protect.eyes,.the.design,.construction,.testing,.and.use.of.protec-
tive..helmets.must.meet.standards.established.by.ANSI..Protective.helmets.purchased.
after.July.5,.1994,.must.comply.with.ANSI.Z89.1-1986.and.they.fall.into.Type.I.under.
the.new.ANSI.Z89.1-1997..Type.II.helmets.must.meet.new.requirements.for.(1).impact.
resistance. from. blows. to. the. front,. back,. sides,. and. top. of. the. head;. (2). off-center.
penetration.resistance;.and.(3).chin.strap.retention..The.old.classes.listed.below.have.
been.changed.to.Class.G.(General),.Class.E.(Electrical),.and.Class.C.(Conductive-no.
electrical.protection)..Hard.hats.are.divided.into.three.industrial.classes:
.
1.. Class.A.now.Class.G:.These.helmets.are.for.general.service..They.pro-
vide. good. impact. protection. but. limited. voltage. protection.. They. are.
used.mainly.in.mining,.building.construction,.shipbuilding,.lumbering,.
and.manufacturing.
