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Subchapter 4. Construction Safety Orders
Article 29. Erection and Construction

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§1717. Falsework and Vertical Shoring.

(a) Design Loads.

(1) Formwork and falsework or shoring for the support of concrete or other materials shall be designed, erected, supported, braced and maintained so as to assure its ability to safely withstand all intended loads during erection, construction, usage and removal.

(2) The minimum total design load for any formwork and shoring shall be not less than 100 pounds per square foot for the combined live and dead load regardless of slab thickness; however, the minimum allowance for live load and formwork shall be not less than 20 pounds per square foot in addition to the weight of the concrete.

When the equipment listed below is used, the above figures shall be increased in all cases by the amounts shown.

Worker propelled carts.... 10 pounds per square foot.

Motorized carts........... 25 pounds per square foot.

(3) Special consideration shall be given and the necessary additional allowances made for any unusual circumstances such as floor hoppers, concentrated piles of reinforcing steel bars, or similar loads.

(4) The lateral loads for shoring to be resisted at each floor in both directions by diagonal bracing, or other means, shall be taken at not less than 100 pounds per lineal foot of floor edge or two percent of the total dead load whichever is greater.

(b) Design.

(1) Detailed design calculations and working drawings shall be approved and signed by a civil engineer, currently registered in California, for all falsework or vertical shoring installations where any of the following conditions exists:

(A) The height, as measured from the top of the sills to the soffit of the superstructure exceeds 14 feet.

(B) Individual horizontal span lengths exceed 16 feet.

(C) Provisions for vehicular or railroad traffic through the falsework or vertical shoring are made.

(2) For all falsework and vertical shoring installations not covered by (b)(1) above, the falsework plan or shoring layout shall be approved and signed by one of the following:

(A) A civil engineer currently registered in California.

(B) A manufacturer's authorized representative.

(C) A licensed contractor's representative qualified in the usage and erection of falsework and vertical shoring.

(3) A falsework plan or a shoring layout shall be available on the job site at all times.

(4) All vertical supports shall be erected on a properly compacted and reasonably level and stable base. Plate, pads and load bearing characteristics of the soil shall be adequate to support the imposed loads.

NOTE: (1) Precautions shall be taken so that weather and concrete pouring conditions do not change the load carrying capacity of the soil below the design minimum.(2) The Division may require that evidence be submitted to justify the design for any falsework or vertical shoring installation.

(c) Inspection.

(1) After construction of the falsework or vertical shoring system enumerated in section 1717(b)(1) and prior to placement of concrete, a civil engineer, currently registered in California, or authorized representative, shall inspect the falsework or vertical shoring system for conformity with the working drawings. The person performing the inspection shall certify in writing that the falsework or vertical shoring system substantially conforms to the workingdrawings and that the material and workmanship are satisfactory.

(2) After construction of the falsework or vertical shoring system enumerated in section 1717(b)(2) and prior to the placement of concrete, an inspection for conformity with the working drawings shall be made by one of the following persons.

(A) A civil engineer currently registered in California.

(B) A manufacturer's authorized representative.

(C) A licensed contractor's representative qualified in the usage and erection of falsework and vertical shoring.

(3) The person performing the inspection shall certify in writing that the falsework or vertical shoring system conforms to the working drawings and that the material and workmanship are satisfactory. The certification shall be available at the job site.

(d) Work Area and Procedures.

(1) Where wood shores are butt spliced, they shall be made with square joints and secured on four sides with not less than 2-inch material or of 5/8-inch plywood of the same width as the post. The scabs shall extend at least two feet beyond the joint.

(2) If metal shore clamps are used, they shall be installed according to manufacturer's specifications.

(3) In lieu of requirements for standard walkways and work platforms in the immediate area where forms are being installed, joists or similar members not less than 5 1/2 inches wide and on centers not to exceed 36 inches shall be provided.

(4) When the formwork and shoring are being erected, the first set of protective guardrails shall be installed at the perimeter immediately after such supporting members are in place. Railings are to be installed and maintained at perimeter of and at openings in all floors of buildings and sides of bridge decks at all times.

(5) In the area immediately adjacent to where the joists or similar members are being installed, a 12-inch wide plank resting on the joists is acceptable as a walkway for distributing joists.

(6) Building floor form installation

(A) Employees shall be prohibited from working below a building floor form installation, except those individuals actually engaged in this installation, removal, or inspection. Warning signs to this effect shall be posted at the perimeter of the affected work area.

(B) During the actual placement of concrete, only those individuals who are engaged in the inspection or necessary building floor form modifications shall be permitted in the affected work area below the concrete placement.

(C) Areas underneath building floor form installations described in sections 1717(b)(1)(A) or 1717(b)(1)(B) shall not be occupied before, during, or after the placement of concrete unless the building floor form installations have been inspected and certified, by a civil engineer currently registered in California, to safely withstand all anticipated loads. All other building floor form installations shall be inspected and certified by one of the following persons, to safely withstand all anticipated loads.

1. A civil engineer currently registered in California.

2. A licensed contractor, or representative, qualified to determine that the floor form installation can safely withstand all anticipated loads.

(7) Stripped forms and shoring shall be removed and stockpiled promptly in all areas in which persons are required to work or pass. Protruding nails, wire ties, and other form accessories not necessary to subsequent work shall be pulled, cut, or other means taken to eliminate the related hazards.

(e) Removal.

(1) Formwork and shores (except those used for slabs on grade and slip forms) shall not be removed until the employer determines that the concrete has gained sufficient strength to support its weight and superimposed loads. Such determination shall be based on compliance with the stipulated conditions for removal of forms and shores indicated in the plans and specifications.

(2) Reshoring shall not be removed until the concrete being supported has attained the strength to support its weight and all loads placed upon it.

NOTE: For regulations relating to permits for falsework, see Section 1503.

NOTE: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.

HISTORY

1. Editorial correction in subsection (b) (Register 70, No. 48).

2. Repealer and new section filed 12-6-73; effective thirtieth day thereafter (Register 73, No. 49).

3. Repealer of subsection (a) new subsections (a), and (d)(8) filed 2-19-75; effective thirtieth day thereafter (Register 75, No. 8).

4. Amendment of subsection (a)(1) filed 5-3-78; effective thirtieth day thereafter (Register 78, No. 18).

5. Amendment filed 6-21-85; effective thirtieth day thereafter (Register 85, No. 25).

6. Amendment of subsection (d)(6) filed 2-15-90; operative 3-17-90 (Register 90, No. 8).

7. New subsection (e) filed 10-22-90; operative 11-21-90 (Register 90, No. 48).

8. Editorial correction of printing error in subsections (d)(6)(B) and (d)(6)(C) (Register 92, No. 19).

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