osha subpart q concrete and masonry construction

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

HScaffolded Side

H + 4 feet

Accessible only to workers actively engaged in constructing the wall. No others are to enter this zone

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.