Environmental Engineering Reference
In-Depth Information
Individual-rung/step.ladders.must.extend.at.least.42.inches.above.an.access.level.
or.landing.platform.either.by.the.continuation.of.the.rung.spacing.as.horizontal.grab.
bars.or.by.providing.vertical.grab.bars.that.must.have.the.same.lateral.spacing.as.the.
vertical.legs.of.the.ladder.rails..Each.step.or.rung.of.a.ixed.ladder.must.be.able.to.
support.a.load.of.at.least.250.pounds.applied.in.the.middle.of.the.step.or.rung.
The. minimum. clear. distance. between. the. sides. of. individual-rung/step. ladders.
and. between. the. side-rails. of. other. ixed. ladders. must. be. 16. inches.. The. rungs. of.
individual-rung/step. ladders. must. be. shaped. to. prevent. slipping. off. the. end. of. the.
rungs.. The. rungs. and. steps. of. ixed. metal. ladders. manufactured. after. March. 15,.
1991,. must. be. corrugated,. knurled,. dimpled,. coated. with. skid-resistant. material,.
or. treated. to. minimize. slipping.. The. minimum. perpendicular. clearance. between.
ixed.ladder.rungs,.cleats,.and.steps.and.any.obstruction.behind.the.ladder.must.be.
7 inches,.except.for.the.clearance.of.an.elevator-pit.ladder,.which.must.be.4
1
/
2
.inches..
The. minimum. perpendicular. clearance. between. the. centerline. of. ixed. ladder.
rungs,.cleats,.steps,.and.any.obstruction.on.the.climbing.side.of.the.ladder.must.be.
30 inches..If.obstructions.are.unavoidable,.clearance.may.be.reduced.to.24.inches,.
provided. a. delection. device. is. installed. to. guide. workers. around. the. obstruction..
The.step-across.distance.between.the.center.of.the.steps.or.rungs.of.ixed.ladders.and.
the.nearest.edge.of.a.landing.area.must.be.no.less.than.7.inches.and.no.more.than.
12 inches..A.landing.platform.must.be.provided.if.the.step-across.distance.exceeds.
12. inches.. Fixed. ladders. without. cages. or. wells. must. have. at. least. a. 15-inch. clear.
width.to.the.nearest.permanent.object.on.each.side.of.the.centerline.of.the.ladder.
Fixed. ladders. must. be. provided. with. cages,. wells,. ladder. safety. devices,. or.
self-retracting.lifelines.where.the.length.of.climb.is.less.than.24.feet.but.the.top.of.
the.ladder.is.at.a.distance.greater.than.24.feet.above.lower.levels..If.the.total.length.
of.the.climb.on.a.ixed.ladder.equals.or.exceeds.24.feet,.the.following.requirements.
must.be.met:.Fixed.ladders.must.be.equipped.with.either.(1).ladder.safety.devices,.
(2) self-retracting.lifelines.and.rest.platforms.at.intervals.not.to.exceed.150.feet,.or.
(e) a. cage. or. well,. and. multiple. ladder. sections,. each. ladder. section. not. to. exceed.
50 feet.in.length..These.ladder.sections.must.be.offset.from.adjacent.sections,.and.
landing.platforms.must.be.provided.at.maximum.intervals.of.50.feet.
The.side-rails.of.through-.or.side-step.ixed.ladders.must.extend.42.inches.above.
the. top. level. or. landing. platform. served. by. the. ladder.. Parapet. ladders. must. have.
an.access.level.at.the.roof.if.the.parapet.is.cut.to.permit.passage.through.it;.if.the.
parapet.is.continuous,.the.access.level.is.the.top.of.the.parapet..Steps.or.rungs.for.
through-ixed-ladder.extensions.must.be.omitted.from.the.extension;.and.the.exten-
sion.of.side-rails.must.be.lared.to.provide.between.24.and.30.inches.of.clearance.
between. side-rails.. When. safety. devices. are. provided,. the. maximum. clearance.
.distance.between.side-rail.extensions.must.not.exceed.36.inches.
Cages.must.not.extend.less.than.27.inches.or.more.than.30.inches.from.the.center-
line.of.the.step.or.rung,.and.must.not.be.less.than.27.inches.wide..The.inside.of.the.
cage.must.be.clear.of.projections..Horizontal.bands.must.be.fastened.to.the.side-rails.
of.rail.ladders.or.directly.to.the.structure,.building,.or.equipment.for.individual-rung.
ladders.. Horizontal. bands. must. be. spaced. at. intervals. not. more. than. 4. feet. apart,.
measured. from. centerline. to. centerline.. Vertical. bars. must. be. on. the. inside. of. the.
