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Concrete & Masonry Construction. Subpart Q. Subpart Q - Concrete & Masonry Construction (1926.700 - 706). Reinforcing steel - Guarding. Masonry walls - Bracing. Masonry construction - Limited access zone. Concrete and Masonry. Revisions to standard during the 1990’s
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Concrete & Masonry Construction Subpart Q OSHA Office of Training & Education
Subpart Q - Concrete & Masonry Construction(1926.700 - 706) Reinforcing steel - Guarding Masonry walls - Bracing Masonry construction - Limited access zone OSHA Office of Training & Education
Concrete and Masonry • Revisions to standard during the 1990’s • Standard expands/toughens protection against wall collapse • Revised bracing requirements • Requires ‘limited access zones’ • Standard focus on guarding of exposed reinforcing steel OSHA Office of Training & Education
Cast-in-Place Concrete • Cast in place concrete must be capable of supporting, without failure: • vertical loads • lateral loads • Use ANSI A10.9-1983 • Drawings and plans • Must be on jobsite • Must include all revisions OSHA Office of Training & Education
Vertical slip-form operation OSHA Office of Training & Education
Cooling TowerSt. Mary’s West Virginia 1978 • 51 killed • 170 feet above ground • Entire form peeled away from newly placed concrete OSHA Office of Training & Education
Jump forms atop the St. Mary’s structure tore loose, pulling work platforms and concrete down inside the tower. OSHA Office of Training & Education
Wreckage 168 feet below the top of the St. Mary’s tower being picked apart by investigators looking for clues. OSHA Office of Training & Education
General Requirements 1926.701 • No construction loads placed on concrete structure unless: • Employer determines safe to do so • Person qualified in industrial design • Structure capable of supporting loads OSHA Office of Training & Education
Concrete and Masonry All reinforcing steel on which an employee may fall must be guarded. OSHA Office of Training & Education
Concrete and Masonry • EVERY rebar must be capped • You are looking at a fine of somewhere between 45 and 250 dollars per instance OSHA Office of Training & Education
ConcreteBucket No employee is ever permitted to ride concrete buckets OSHA Office of Training & Education
Working under loads • No employee shall work under concrete bucket while: • Bucket is being raised • Bucket is being lowered • To the extent practical… route buckets so no employees or the fewest number are exposed OSHA Office of Training & Education
Concrete Buckets • If equipped with hydraulic or pneumatic gates, must: • Have safety device • to prevent premature or • accidental dumping. • Shall be designed to prevent concrete from hanging up on top & sides. OSHA Office of Training & Education
Concrete pumping systems • Provided with pipe supports designed for 100% overload • Compressed air hoses on pumping systems: • Positive fail-safe joint connectors • Prevent separation of sections while pressurized OSHA Office of Training & Education
Personal Protective Equipment • If pneumatic hose is used to pump cement sand and water mixture • Employees must wear head and face and eye protection. OSHA Office of Training & Education
Bulk cement storage safety • Storage bins and silos: • Conical or tapered bottoms • Concrete Mixers: • Mechanical device to clear material • Guardrails on each side • No employee permitted to enter unless ejection system shut down / locked & tagged out so system can’t operate. OSHA Office of Training & Education
Power concrete trowels Dead-man control: • Stop automatically when hand(s) are released from control OSHA Office of Training & Education
Bull floats • If handles could contact electrical conductors they must be of the non- conductive type OSHA Office of Training & Education
Guarded with semi-circular enclosure over blade • Enclosure must provide for retaining flying blade fragments OSHA Office of Training & Education
Do You See Any Violations?? OSHA Office of Training & Education
Vertical slip forms • Rods or pipes on which jacks climb: • Designed for that purpose • No excessive distortion during jacking • Provided with scaffolds where employees are required to pass OSHA Office of Training & Education
Removal of formwork • Forms and shores (Except those used for slabs on grade & slip forms): • Not removed until Employer determines concrete has gained sufficient strength to support its weight and superimposed loads OSHA Office of Training & Education
CFR 1926.706Masonry Construction. OSHA Office of Training & Education
Concrete and Masonry • Masonry wall construction • Need a “limited access zone”
Limited Access Zone (LAZ) • Shall be established whenever masonry wall is being constructed • Prior to start of wall construction OSHA Office of Training & Education
Limited Access Zone (LAZ) • Height of wall plus 4’ • Entire length of wall • On un-scaffold side • Restricted entry • Masons ONLY!
Limited Access Zone • Shall remain in place until wall is supported • If wall is over 8’ tall it must be braced • Bracing must remain until permanent support structures are in place OSHA Office of Training & Education
Build Safely.... Build SAFETY!! OSHA Office of Training & Education