Transcript OSHA Subpart Q

OSHA Subpart Q
Concrete and Masonry
Construction
Concrete Construction
• Protruding reinforcing steel, onto and into
which employees could fall, shall be
guarded to eliminate the hazard of
impalement
Post-tensioning Operations
• No employee shall be permitted to be
behind the jack during tensioning
operations, except those essential to the
jacking operation
• Use signs and barriers to limit employee
access to post-tensioning area during this
operation
Placing Concrete with Buckets
• Riding Concrete Buckets is not permitted
Placing Concrete with Buckets
• Working under the buckets is not permitted
when they are elevated or lowered into
position
Placing Concrete with Buckets
• Route elevated concrete buckets so no
employees (or as few employees as possible)
are exposed to the hazards of falling concrete
buckets
Pumping Concrete
• Operator of the pneumatic hose must wear
proper protective head and face equipment
Bulk Cement Storage
• Storage bins to have tapered or conical
bottoms
• No employee is permitted in the storage
facility unless the ejection system is shut
down, locked out, and tagged.
Power Concrete Trowels
• Powered, but manually guided, trowels shall
be equipped with a control switch that will
automatically shut off the power whenever
the hands of the operator are removed
Concrete Buckets with Hydraulic
or Pneumatic Gates
• Shall be equipped with positive safety
latches or similar devices to prevent
premature or accidental dumping
Bull Floats
• If used near energized electrical conductors,
bull floats shall be constructed of
nonconductive material or insulated with a
nonconductive sheath.
Cast-in-Place Concrete
• Formwork shall be designed and
constructed so that the forms will be
capable of supporting, without failure, all
vertical and lateral loads that can be
reasonably anticipated.
Cast-in-Place Concrete
• Shores and reshores shall be inspected prior
to use.
• Erected shoring equipment shall be
inspected immediately prior to, during, and
immediately after concrete placement.
Cast-in-Place Concrete
• Sills for shoring shall be sound, rigid, and
capable of carrying the maximum intended
load.
When to inspect formwork
shoring:
• Immediately prior to concrete placement
• During concrete placement
• Immediately after concrete placement
Shoring for Formwork
• Sills for shoring shall be sound, rigid, and
capable of carrying the intended load
• There shall be no eccentric loads on shore
heads, unless for this purpose
Single post shores when used on
top of another (tiered)
• The system shall be designed by a qualified
design
• The erected system shall be inspected by an
engineer qualified in structural design
• Single post shores shall be vertically aligned
• Single post shores are not to be raised after
concrete is placed
Reshoring
• Reshores are to be put in place as the
original forms and shores are removed
• Reshores are required when the concrete
cannot support the loads
Vertical Slip Forms
• Steel rods and pipes on which jacks climb
or by which the forms are lifted shall be
designed for the purpose
• Shall be provided with scaffolds or work
platforms where employees are required to
work or pass
• Loads shall not exceed the rated loads of the
jacks
Vertical Slip Forms
• The jacks or lifting devices shall be
equipped with mechanical dogs or
automatic holding devices to support the
slip forms when the power supply or lifting
mechanism fails
• Do not exceed the predetermined safe rate
of lift
Reinforcing Steel
• Reinforcing steel for wall, piers, columns
and similar vertical structures shall be
adequately supported to prevent overturning
• Prevent unrolled wire mesh from recoiling
Removal of Formwork
• Forms and shores (except slab on grade and
slip forms) shall not be removed until the
concrete has gained sufficient strength to
support its weight and superimposed loads
•
According to the plans and specs
•
Concrete strength has been tested
•
Don’t remove reshores until concrete
strength is adequate
Precast Concrete
• Includes wall units, structural framing and tilt-up
wall panels
• Shall be adequately supported to prevent
overturning and collapse
• Lifting inserts (tilt-up panels) shall be capable of
carrying twice the intended load
• Lifting inserts (members other than tilt-up) shall
be capable of carrying four times the intended load
• Lifting hardware to carry 5 times the intended load
Placing Concrete Members
• No employees hall be permitted under
precast concrete members being lifted or
tilted into position
• Exception, employees required to be so
located for the erection of those members
Lift Slab Construction
• Designed by a registered professional engineer
• Jacks to support 2.5 times the load being lifted
• All jacking points shall stay within 1/2” of
that needed to maintain the slab in a level
position
• Only essential jacking personnel permitted in
the structure when jacking is taking place
Masonry Construction
• Limited Access Zone - To be established
whenever a masonry wall is constructed
Limited Access Zone
• Established prior to beginning construction
of the wall
• Runs the length of the wall
• Horizontal projection that is equal to the
wall height plus 4 feet
• Established on the side of the wall that is
not scaffolded
Limited Access Zone
Accessible only to workers
actively engaged in constructing
the wall. No others are to enter
this zone
H
Scaffolded
Side
H + 4 feet
Limited Access Zone
• Must remain in place until the wall is
adequately supported to prevent overturning
• If over 8 feet in height, the zone is to remain
in place until the wall is adequately braced
to prevent overturning. The bracing is to
remain in place until the permanent
supporting elements of the structure are in
place.