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(a) All elevator shafts in which cages are not installed and which are not enclosed with solid partitions and doors shall be guarded on all open sides by standard railings and toeboards.
(b) Overhead protection shall be provided at all times when persons are employed in the shaft and other workmen area above them.
(c) In a shaft, if one elevator is put into service before the others are completed, such elevator(s) in use shall be separated from the other elevators by a continuous partition of solid material, or a wire screen with mesh not larger than 2 inches.
(d) Temporary platforms, such as false cars, shall cover approximately the full area of the shaft. Standard railings shall be provided when opening between platform and structure exceeds 16 inches.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 1635. Floors, Walls and Structural Steel Framed Buildings.
(a) For multifloor buildings, other than structural steel framed buildings, the following shall apply:
(1) Every building shall have the joists, beams, or girders of floors below the floor or level where any work is being done, or about to be done, covered with flooring laid close together, or with other suitable material to protect workers engaged in such building from falling through joists or girders, and from falling substances, whereby life or safety is endangered.
(2) Every building which is of reinforced concrete construction, with reinforced concrete floors, shall have the floor filled in, either with forms or concrete, on each floor before the commencement of work upon the walls of the second floor above or the commencement of work upon the floor of the next floor above.
(3) Every building having wooden floors other than a steel frame building shall have the underflooring, if double flooring is to be used, laid on each floor within the time prescribed above for reinforced concrete floors. Where single wooden floors are to be used, each floor shall be planked over within the time prescribed above for reinforced concrete floors.
(4) If a span of a floor on a building exceeds 13 feet, an intermediate beam shall be used to support the temporary flooring, but spans not to exceed 16 feet may be covered by three-inch planks without an intermediate beam. The intermediate beam shall be of a sufficient strength to sustain a live load of 50 pounds per square foot of the area supported.
(5) If building operations are suspended and the temporary flooring required by this article is removed, the building shall be replanked upon the resumption of work so that every worker at work has a covered floor not more than two stories below.
(6) Planked floors on buildings shall be tightly laid together of proper thickness, grade and span to carry the working load; such working load to be assumed as at least 25 pounds per square foot.
(7) Fall protection shall be required in accordance with Article 24.
(8) No person shall proceed with any work assigned to or undertaken or require or permit any other person to proceed with work assigned to or undertaken by either, unless the planking or nets required by this article are in place.
(b) For multifloor structural steel framed buildings more than two stories high, the following shall apply: These provisions shall apply to buildings erected in tiers or stories and shall not apply to steel framed buildings having large open spans or areas such as, mill buildings, gymnasiums, auditoriums, hangars, arenas, or stadiums.
(1) The derrick or working floor of every building shall be solidly decked over its entire surface except for access openings.
(2) There shall be a tight and substantial temporary floor within two floors below and directly under that portion of each tier of beams on which erection, riveting, bolting, welding or painting is being done. For operations of short duration of exposure to falling, fall protection shall be required as set forth in Article 24 and Section 1710.
(3) Temporary floors shall be wood planking of proper thickness, grade and span to carry the working load, but shall not be less than two inches thick, full size undressed.
(4) Provision shall be made to secure temporary flooring against displacement by strong winds or other forces.
(5) Planks shall extend a minimum of 12 inches beyond centerline of their supports at each end.
(6) Wire mesh or plywood (exterior grade) shall be used to cover openings adjacent to columns where planks or metal decking do not fit tightly. The materials used must be of sufficient strength as required by Section 1632(b) to provide fall protection for personnel and prevent objects from falling through.
(7) Metal decking where used in lieu of wood planking shall be of equivalent strength and shall be laid tightly and secured to prevent movement.
(8) Floor planks or metal decking that are temporarily removed for any reason whatsoever shall be replaced as soon as work requiring their removal is completed or the open area shall be properly guarded.
(9) Prior to removal of temporary floor planks or metal decking, employees shall be instructed by assigned supervision the steps to be taken to perform the work safely and in proper sequence.
(10) When gathering and stacking temporary floor plank on a lower floor, in preparation for transferring such plank for use on an upper working floor, the steel erector's personnel shall remove such plank successively, working toward the last panel of such floor, so that the work is always being done from the planked floor.
(11) When gathering and stacking temporary floor planks from the last panel, the steel erector's personnel assigned to such work shall be protected by a personal fall protection system used in accordance with Article 24 and Section 1710.
(12) The sequence of erection, bolting temporary guying, riveting and welding shall be such as to maintain the stability of the structural frame at all times during construction. This applies to the dead weight of the structure, plus weight and working reactions of all construction equipment placed thereon plus any external forces that may be applied.
(13) Where a building is being constructed in sections, each section constitutes a building.
(14) Personal fall protection and nets shall be required in accordance with Article 24 and Section 1710.
(15) No person shall proceed with any work unless the planking and metal decking, or nets required by this article are in place.
(c) Special Provisions Applicable to Floor Openings. Section 1632(b) applies to floor openings at locations where steel erection work is taking place. This subsection applies where work is in progress that requires floor openings to be uncovered. For such work, all of the following requirements shall apply:
(1) The floor or working level where such work is in progress shall be under the exclusive control of the steel erection employer and shall be barricaded to prohibit entry by unauthorized personnel.
(2) The floor area adjacent to the floor opening shall be barricaded or the floor opening shall be covered when not attended by steel erection personnel.
(3) All planking and other materials used to cover floor openings shall be capable of safely supporting the greater of 400 pounds or twice the weight of the employees, equipment and materials that may be imposed on any one square foot area of the cover at any time. The cover shall have not less than 12 inches of bearing on the surrounding structure.
(4) All floor opening covers shall bear a sign stating, "OPENING-DO NOT REMOVE", in 2 inch high, black bold letters on a yellow background.
(5) The placement of covers shall be verified by a qualified person prior to each shift and following strong wind conditions.
(6) Workers shall be instructed and required to adhere to the following:
(A) Keep covers in place when not engaged in work requiring the opening to be uncovered, and
(B) Never remove a cover by walking forward or by stepping into an area where they cannot directly observe the surface their feet will touch.
(7) After work requiring floor openings to be uncovered has been completed and prior to allowing other trades in the work area, the guarding and covers for floor openings shall meet the provisions of Section 1632(b).
Note: Authority cited: Section 142.3, Labor Code. Reference: Sections 142.3, 7101, 7102, 7103, 7104, 7105, 7107, 7108, 7109, 7251, 7252, 7253, 7254, 7255, 7256, 7257, 7258, 7259, 7261, 7262, 7263, 7264, 7265 and 7266, Labor Code.
s 1635.1. Permits.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 1636. Periphery Railings on Buildings.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 1637. General Requirements.
(a) Scaffolds shall be provided for all work that cannot be done safely by employees standing on permanent or solid construction at least 20 inches wide, except where such work can be safely done from ladders. Exceptions: 1. Work of a limited nature and of short duration when the permanent or solid construction is less than 20 inches in width and the fall distance does not exceed 15 feet in height and provided adequate risk control is recognized and maintained under competent supervision. 2. Work of a short duration from joists or similar members at 2 feet or closer centers, planks resting on these members forming a plank platform 12 inches wide or equivalent protection.
(b) Scaffold Design and Construction.
(1) Scaffolds shall be constructed of wood or other suitable materials such as steel or aluminum members of known strength characteristics. Where materials other than wood are used, or where scaffold designs differ from those specified in these Orders, the scaffold and its parts must provide a degree of strength, rigidity and safety equivalent to that provided by the described scaffold it replaces.
(2) Each scaffold shall be designed and constructed using a dead load safety factor that will ensure the scaffold supports, without failure, its own weight and 4 times the maximum intended working (live) load applied or transmitted to it. Maximum intended working loads shall be as follows:
(A) Light-duty scaffolds: 25 pounds per square foot of work platform.
Exception: Light-duty interior scaffolds shall adhere to the loading requirements contained in Section 1640(c)(1).
(B) Medium-duty scaffolds: 50 pounds per square foot of work platform.
(C) Heavy-duty scaffolds: 75 pounds per square foot of work platform.
(D) Special-duty scaffolds: exceeding 75 pounds per square foot of work platform as determined by a qualified person or a Civil Engineer currently registered in the State of California and experienced in scaffold design.
(E) Engineered scaffolds: as determined by a Civil Engineer currently registered in the State of California and experienced in scaffold design.
(3) A scaffold shall not be subjected to loads greater than its maximum intended working load (see 1637(b)(2)).
(4) Manufactured scaffolds shall be used in accordance with the manufacturer's recommendations.
(5) A qualified person shall determine the maximum intended working loads for scaffolds that are neither manufactured nor engineered.
(6) The maximum intended working load for each scaffold shall be posted at a conspicuous location at each jobsite or be provided to each supervisory employee who shall have it readily available at the jobsite.
(c) Anchorage and bracing shall be such that scaffolds and falsework will be prevented from swaying, tipping, or collapsing.
(d) Scaffold lumber, except for planks, used on suspended or ladder-jack scaffolds, shall be the equivalent of "selected lumber," free from damage that affects its strength. (See definitions for lumber specifications.)
(e) (1) Extension planking of the finger type shall be made with at least 5 fingers on each side. These fingers shall be at least 1-inch by 2 1/8-inch selected straight-grained Douglas fir or material of equal strength. All metal fittings shall be adequate to maintain the structural qualities of the device.
(2) The length of the extended planking shall not exceed 12 feet 6 inches, and the actual mechanical overlap between the 2 halves shall be not less than 1/8 of the length of the extended planking. A substantial stop shall be provided to maintain this overlap.
(3) Not more than one employee shall be permitted at one time on any extension planking that is more than 3 feet in height.
(4) Extension planking shall not be used as a platform on ladder-jack, suspended, or other unstable scaffolds.
(f) (1) Except as specified in other Orders, all planking shall be at least equivalent to 2-inch x 10-inch (nominal) lumber selected for scaffold grade plank as defined in Section 1504, Lumber - "Structural Plank."
(2) The maximum permissible spans for 2 x10-inch (nominal) or 2 x9-inch (rough) planks shall be as shown in the following Table:
__________________________________
Working Load (psf)........... 25 .. 50 .. 75
Permissible Span (ft.)....... 10 .. 8 ... 7
__________________________________
(3) Manufactured planks with spans in excess of 10 feet shall be labeled to indicate the maximum safe working load based on a safety factor of four.
(4) All planks shall be capable of safely sustaining the intended load.
(g) Except as specified in other Orders, a scaffold plank shall not overhang its support by more than 18 inches, unless access to this overhanging portion is prevented by a guardrail, or other barrier, or unless the other plank end is securely anchored.
(h) Inspection of Lumber. All scaffold lumber shall be visually inspected for defects before and during use. Defective lumber shall not be used.
(i) (1) Nailing. All nailed joints in scaffolds and wooden falsework must contain enough properly placed nails of ample size to carry the loads they are intended to support.
(2) Nailed joints or connections shall not be used to support concrete hoppers with a capacity in excess of 1/2 cubic yard.
(3) Double-headed nails shall not be used for attaching railings or in other service where the projections might catch on the clothing of workers or create similar hazards.
(4) No nail smaller than 8-penny shall be used in the construction of scaffolding.
(5) All nails shall be driven full length or to the first head when double-headed nails are used.
(6) The minimum number of nails per connection shall be in accordance with the following table:
1 "x6 " Material .. 1 "x8 " Material .. 2 " Material
Ledgers ........... 4-8d .............. 5-8d .......... 2-16d
Ribbons ........... 3-8d .............. 3-8d
Braces ............ 3-8d .............. 3-8d .......... 2-16d
Guardrails ........ 2-8d .............. 2-8d .......... 2-16d
(7) Lubricated or wax-coated nails shall not be used in the construction of scaffolds, falsework, or other temporary installations.
(j) Prohibited Types of Scaffolds. Lean-to or jack scaffolds, shore scaffolds, nailed brackets, loose tile, loose brick, loose blocks, stilts, or other similar unstable objects shall not be used as working platforms, or for the support of such platforms. See Plate B-40, Appendix.
Exception: Bricklayer'sBricklayer's "jump boards" no higher than 20 inches above the regular scaffold platform are acceptable for such service when supported by piers of carefully piled bricks or concrete blocks.
(k) Erection and Dismantling.
(1) The erection and dismantling of scaffolds or falsework shall be performed under the supervision and direction of a qualified person. Note:In addition to persons meeting the requirements of "qualified persons" as defined in Section 1504, person(s) possessing a certification of competence in scaffold erection, dismantling and use issued by trade associations, State-approved apprenticeship or training programs or other similar training programs shall be considered a "qualified person(s)."
(2) Erection and dismantling of scaffolds shall be performed in accordance with good engineering practice. Where engineering design is required by these orders, the engineering drawings shall be made available at the job site during erection or upon request by the Division.
(3) All required ties to the structure shall be installed as soon as the scaffold has been completed to the tie-in area during erection.
(4) Ties shall only be removed during dismantling as the work progresses downward unless other methods are used to prevent the scaffold from falling over.
(5) No structural members shall be removed from scaffolds during dismantling operations below the level being dismantled.
(6) Where work platforms are proposed, guardrails shall be installed before other work not directly related to scaffold erection is permitted to begin.
(7) The requirements of Section 1637(k) (2) through (6), inclusive, may be temporarily suspended for short durations, provided adequate risk control is recognized and maintained under immediate, competent supervision.
(l) Removal of Braces. Scaffolds or falsework installations shall not be altered by removing uprights, braces, or supports unless other members providing equivalent strength are substituted.
(m) Loading. Scaffolds shall not be overloaded. Material shall not be allowed to accumulate to the extent that a scaffold is subjected to loading it is not designed to support.
(n) Access.
(1) A safe and unobstructed means of access, such as a walkway, stair, or ladder shall be provided to all scaffold platforms.
(2) Climbing ladders or stairways on scaffolds used for access and egress shall be affixed or built into the scaffold by proper design and engineering, and shall be so located that their use will not disturb the stability of the scaffold.
(A) Manufactured hook-on and attachable ladders shall be securely attached to the scaffold and:
1. Shall be specifically designed for the type of scaffold used;
2. Shall have a minimum rung length of 11-1/2 inches (29 cm); and
3. Shall have uniform spaced rungs with a maximum spacing between rungs of 16- 3/4 inches.
(B) If a ladder is used as a means of access to the scaffold, it shall be securely attached and shall comply with Article 25 of the Construction Safety Orders.
(C) Permanent stairways shall comply with the applicable provisions of the General Industry Safety Orders. Prefabricated scaffold steps or stairs, manufactured on or before May 28, 2005, shall comply with the design, manufacture and installation requirements of either the American National Standard ANSI A10.8-1988, Scaffolding-Safety Requirements, or the ANSI/ASSE A10.8-2001, Safety Requirements for Scaffolding, which are hereby incorporated by reference. Prefabricated scaffold steps or stairs, manufactured after May 28, 2005, shall comply with the design, manufacture and installation requirements of ANSI/ASSE A10.8-2001, Safety Requirements for Scaffolding.
(D) Horizontal members of end frames may be designed and used as a climbing device provided that the steps are:
1. Reasonably parallel and level.
2. Arranged to form a continuous ladder as required in Section 1644(a)(8).
3. Provided with sufficient clearance to provide a good handhold and foot space.
(o) Sloped Platforms. Platforms shall not be sloped more than 2 feet vertically to 10 feet horizontally and shall be positively secured against slipping from supports.
(p) Slippery Conditions. No worker shall be permitted to work on a scaffold platform where slippery conditions exist unless such conditions are a necessary part of the work.
(q) Overhead Protection. Workers on scaffolds who are exposed to overhead hazards shall be provided with overhead protection or other means that will effectively eliminate the hazard.
(r) Bolted Connections. Bolts used in the construction of scaffolds shall be of a size and in sufficient numbers at each connection to develop the designed strength of the scaffold. (See Plate B-31, Appendix.)
(s) Hoisting of Materials. Where materials are line-hoisted onto a scaffold, a tag line shall be used where necessary to control the load.
(t) Platform Planks at Corners. When a scaffold materially changes its direction, the platform planks shall be laid to prevent tipping. The planks that meet the corner ledger at an angle shall be laid first, extending over the diagonally placed ledger far enough to have a good safe bearing, but not far enough to involve any danger from tipping. The planking running in the opposite direction at an angle shall be laid so as to extend over and rest on the first layer of planking.
(u) Work on or from scaffolds is prohibited during storms or high winds unless a qualified person has determined that it is safe for employees to be on the scaffold and those employees are protected by a personal fall arrest system, as defined in Section 1504 of these Orders, or wind screens. Wind screens shall not be used unless the scaffold is secured against the anticipated wind forces imposed.
(v) Wood platforms shall not be covered with opaque finishes, except that platform edges may be covered or marked for identification. Platforms may be coated periodically with wood preservatives, fire-retardant finishes, and slip-resistant finishes; however, the coating may not obscure the top or bottom wood surfaces.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 1640. Light-Duty Wooden Pole Scaffolds.
(a) Pole scaffolds to be used by carpenters, lathers, shinglers, painters, plasterers, sheet metal workers, or other trades not using heavy tools or storing heavy materials on the scaffolds, shall be constructed as follows:
(See Plate B-18, Appendix)
(b) Light-Duty Exterior Scaffolds.
(1) Uprights. For heights not to exceed 20 feet, the uprights shall be 2-inch by 4-inch lumber or heavier, spaced not more than 3 feet between uprights at right angles to the wall and not more than 10 feet center to center, parallel to the wall. The inside uprights may be omitted and ledgers attached to the permanent structure, provided that the method of attaching the ledgers to the permanent structure will make the connection as secure as though the ledger were nailed to the upright with 5 8-penny nails. The splices of uprights shall be made with square butt joints, and scabs of 1-inch by 4-inch or heavier material at least 48 inches long shall be nailed on 2 sides of each upright with 6 nails in each 1/2 of each scab. If the uprights of the scaffold rest on a surface that might cause slipping, a continuous sill or other means shall be provided to hold the uprights in place. When the scaffold is resting on earth or other such material, the uprights shall rest on and be secured to the equivalent of a 2-inch by 10-inch by 10-inch wooden base. Note:1 1/8-inch by 10-inch by 10-inch piece of exterior grade plywood may be used in lieu of the wooden base mentioned above.
(2) Ledgers and Ribbons. The platforms of the scaffold shall be supported by ledgers. For ledgers spanning not more than 3 feet between uprights, use 2 pieces of 1-inch by 6-inch board, 1 being on each side of the uprights and fastened securely at each point of support. Single 2-inch by 4-inch ledgers are not permitted. Vertical spacing of ribbons and ledgers shall not exceed 7 feet. The ribbons shall be 1-inch by 6-inch or heavier material, placed on the outer uprights, directly under, and in contact with, the ledgers. The ribbons shall be long enough to extend from upright to upright without splices. Exceptions: 1. When metal ledgers are used or when ledgers are bolted or when a 45-degree angle brace is nailed to the uprights between double ledgers, and ledgers also nailed to this brace, the ribbon may be placed at other elevations such as guardrail height, but they cannot be eliminated from the scaffold. 2. Metal ledgers and ribbons that are part of a patented scaffold system may be used when installed in accordance with the manufacturer's instructions.
(3) Ties and Braces. The scaffold shall be securely tied to the building or structure by means of a double looped No. 12 iron wire, or single looped No. 10 iron wire or 1-inch by 4-inch boards with at least 2 nails at each connection or equivalent means. Ties shall connect to the inside uprights and shall not be more than 20 feet apart horizontally and vertically. The outside line of uprights shall contain sufficient diagonal bracing of 1-inch by 6-inch material in a vertical plane across the entire face of the scaffold in both directions to prevent swaying, tipping, or collapsing. (See Appendix Plate B-18).
Exception: Bracing of 2-inch by 4-inch material may be used provided that the bracing extends from ledger to next higher or lower ledger or from ledger to sill in the form of an "X" in the end bays and in every third bay in between so that the "X" bracing also extends from the upper-most ledger to the sill, vertically, in each of these bays.
(4) Railing. Open sides and ends of intermediate working levels 7 1/2 feet or more above grade shall be guarded by a 2-inch by 4-inch top rail nailed to the uprights so that the top edge is between 42 inches and 45 inches above the platform. Midrails of at least 2-inch by 4-inch material are required at all work levels. The uppermost platform shall be protected by a top rail consisting of double 2-inch by 4-inch members. One member shall be fastened in a flat position on top of the uprights and the other member shall be fastened in an edge-up position to the inside of the uprights and at the side of the top member. A single 2-inch by 4-inch member having an allowable bending stress of at least 1,900 psi may be used as a top rail.
(5) Platforms.
(A) Platform planks shall be of 2-inch by 10-inch or larger material and of such length that they overlap the ledgers at each end by at least 6 inches. A plank shall not overlap an unsupported end of another plank. The working platform shall cover the entire space between scaffold uprights, except for the open area under the backrailing, which shall not be more than 8 inches wide. Platforms shall be at least 20 inches wide and within 14 inches of the structure wall. When moving platforms to the next level, the old platform shall be left undisturbed until the new ledgers have been set in place ready to receive the platform planks.
Exception: A single 2-inch by 10-inch plank may be used for light trades work up to a height of 4 feet.
(B) Working platforms for light-trades work may be made of 3/4-inch Douglas fir plywood instead of 2-inch plank if the platform is at least 2 feet wide, nailed in place and supported on cross members at 4-foot or closer intervals along its length.
(c) Light-Duty Interior Scaffolds.
(1) Loading. For scaffolds of the following design, the imposed load on the platform area shall not apply more than 1,500 pounds to any 1 ledger or a single upright, and the total load on the whole platform area shall not average more than 15 pounds per square foot.
(2) Uprights.
(A) For heights not to exceed 20 feet the uprights shall be 2-inch by 4-inch lumber, or heavier. For heights between 20 feet and 60 feet, the uprights shall be 3-inch by 4-inch lumber, or heavier, except for the top 20 feet which may be 2-inch by 4-inch material. The horizontal distance between uprights shall not exceed 10 feet measured either parallel or at right angles to the direction of the platform planks.
(B) If uprights are spliced, the joints must conform to that described in subsection 1640(b)(1), and they shall be located near a point where ribbons are attached or where equivalent lateral support is provided. Pairs of horizontal ribbons at right angles to one another are required at vertical intervals of 7 feet, or less.
(3) Ledgers and Ribbons. The platform of the scaffold shall be supported by ledgers made of one piece of 2-inch by 10-inch or heavier material, placed with the edge upward. The ribbons shall be 1-inch by 6-inch or heavier material, placed on all uprights directly under and in contact with the ledgers. Additional horizontal ribbons, in pairs at right angles to one another, shall be provided at lower levels in order to provide lateral support for all uprights at vertical intervals not greater than 7 feet.
(4) Diagonal Braces. Each line of uprights shall contain sufficient diagonal bracing of 1-inch by 6-inch material in vertical planes, lengthwise and crosswise, to prevent swaying, tipping, or collapsing. If the scaffold extends to and bears against the walls of the building, the horizontal ribbons and ledgers may provide adequate support without diagonal braces, but provision must always be made for adequate lateral stability.
(5) Platforms.
(A) The platform shall consist of 2-inch by 10-inch or larger planks laid closely together. There shall be no other openings in the platform except those necessary for the passage of employees and material. Unless nailed in place, planks shall be of such length that they overlap the ledgers at each end by at least 6 inches. A plank shall not overlap an unsupported end of another plank.
(B) Working platforms shall cover the entire space between scaffold uprights, except for the open area under the backrailing which shall not be more than 8 inches.
(C) Platforms shall extend within 14 inches of the finished face of the building.
(D) Douglas fir plywood that is 3/4 inch thick, or thicker, may be used for platforms if the panels are 4 feet wide, or wider, and are supported on ledgers or crossmembers at 4-foot or closer intervals.
(6) Railings. Open sides of working levels 7 1/2 feet or more above grade shall be provided with top rails and midrails as specified in Subsection 1640(b)(4). When scaffold platforms are erected in sections it is necessary for workers to travel between these sections, such sections shall be provided with connecting runways equipped with railings as described in Section 1620.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 1641. Heavy-Trade Wooden Pole Scaffolds.
(a) Pole scaffolds to be used by bricklayers, stonemasons, concrete workers, or other trades using heavy tools or storing heavy material on the scaffold shall be constructed as follows:
(See Plate B-19, Appendix):
(b) When buggies are used on scaffolds to transport concrete, a strong scaffold shall be designed that is capable of supporting a concentrated load equal to the weight of a loaded buggy at any point on girders, beams, or planking.
(c) Uprights. For heights not to exceed 20 feet, the uprights shall be of 4- inch by 4-inch lumber or heavier material, with a space of 4 feet between uprights at right angle to the wall and not more than 7 feet, center to center, parallel to the wall. The splices of 4-inch by 4-inch uprights shall be made with square butt joints, and scabs of 2-inch by 4-inch material at least 48 inches long shall be nailed in place on 2 sides with 6 nails in each 1/2 of each scab. Uprights laminated from 2-inch by 4-inch material are acceptable if the joints of each lamination are staggered, and either reinforced by scabs or so arranged that they occur at or near ribbon attachment points. If the uprights rest on a surface that might cause slipping, a continuous sill or other means shall be provided to hold the up rights in place. When the scaffold is resting on earth or other such material, the uprights shall rest on and be secured to the equivalent of a 2-inch by 10-inch by 10-inch wooden base.
Note: A 1 1/8-inch by 10-inch by 10-inch piece of exterior grade plywood may be used in lieu of the wooden base mentioned above.
(d) Ledgers and Ribbons.
(1) The platform shall be supported by ledgers and ribbons, nailed or bolted to the uprights. For ledgers spanning not more than 4 feet between uprights, use either 1 piece of 2-inch by 6-inch lumber securely fastened at each point of support or 2 pieces of 1-inch by 6-inch board, 1 being on each side of the uprights and fastened securely at each point of support.
(2) Ribbons shall be 1-inch by 6-inch or heavier material securely fastened to both inside and outside uprights directly under and in contact with the ledgers. Vertical spacing of ribbons and ledgers shall not exceed 7 feet. Ribbons shall be long enough to extend from upright to upright without splices.
(e) Railing. Open sides and ends of working levels 7 1/2 feet or more above grade shall be provided with top rails and midrails as specified in subsection 1640(b)(4).
Exception: That side of bricklayers' and masons' scaffolds adjacent to the work under construction provided that the wall is higher than the adjacent work platform.
(f) Ties and Braces.
(1) The scaffold shall be rigidly tied to the building or structure by means of a double looped No. 12 iron wire, or single looped No. 10 iron wire or equivalent or stronger material used in combination with spacer blocks between inside uprights and the structure. Ties shall connect to the inside uprights, and they shall be not more than 15 feet apart vertically or horizontally.
(2) The entire scaffold shall be rigidly braced with 1-inch by 6-inch boards, and every part thereof so secured as to prevent swaying, tipping, or collapsing. The diagonal bracing shall extend in both directions across the entire outside vertical face. (See Appendix Plate B-19.)
(g) Platforms.
(1) The platform shall be not more than 4 feet wide, constructed of planks at least 2 inches thick and 10 inches wide, laid closely together. Platform planks that are butt-ended (not overlapped) must be nailed to ledgers consisting of 2- inch by 6-inch or heavier material. If the planks are not nailed, they shall be of such length that they overlap the ledgers at each end by at least 6 inches. A plank shall not overlap an unsupported end of another plank. The working platform shall cover the entire space between scaffold uprights except for the open area under the backrailing, which shall not be more than 8 inches.
(2) Platforms shall extend within 14 inches of the finished face of the building, except those used primarily by bricklayers and stonemasons shall extend to within 7 inches of the finish face of the building on which the work is being performed.
(3) When moving platforms to the next level, the old platform shall be left undisturbed until the new ledgers have been set in place ready to receive the platform planks.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 1642. Schedules of Timber Scaffolds up to 60 Feet in Height.
(Listed lumber sizes are those required for the specified spans; other sizes may be used for different spans, if equivalent strength is provided.)
Light ...... Heavy
Interior .... Trades ..... Trades
Uprights for scaffolds
not over 20' in height.................. 2'x4' ....... 2'x4' ...... 4'x4'
Uprights for scaffolds 20'
to 60' in height........................ 3'x4' ....... 3'x4' ...... 4'x6'
Ribbons directly under ledgers.......... 1'x6' ....... 1'x6' ...... 1'x6'
Ledgers................................. 2'x10' ...... 2-1'x6' .... 2-1'x6'
or 1-2'x6'
Spacing uprights, transverse,
at right angles to platform planks...... 10' ......... 3' in clear 4' in clear
Spacing uprights, longitudinal,
parallel t direction of platform
planks.................................. 10' ......... 10' ........ 7'
Spacing ribbons or ledgers,
vertical................................ 7'0' max..... 7'0' max.... 7'0' max.
Splice pieces 48' long
(for uprights).......................... 2-1'x4' or .. 2-1'x4' or
2-2'x4'
(2-2'x4') ... (2-2'x4')
Braces.................................. 1'x6' ....... 1'x6' ...... 1'x6'
RAiling................................. 2'x4' ....... 2'x4' ...... 2'x4'
Toeboard................................ 1'x4' ....... 1'x4' ...... 1'x4'
Width of platform....................... 10' ......... 3' max...... 4' max.
Planking.................................... 2' thick and at least 10' wide
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 1643. Scaffolds over 60 Feet in Height.
All wooden pole scaffolds over 60 feet in height shall be designed by a Civil Engineer currently registered in California and constructed and erected in accordance with such design.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 1644. Metal Scaffolds.
(a) General.
(1) Metal scaffolds shall be designed to support all dead, live, and wind loads to which they will be subjected.
(2) No metal scaffold equipment that is broken or deteriorated to the extent that its section is structurally weakened shall be used.
(3) All stationary scaffold legs, including those of outriggers, shall rest upon base plates available from the manufacturer for this service. Each base plate shall have support adequate to sustain the load and prevent horizontal movement. When the scaffold or outrigger is resting on earth or soft material, the base plate shall rest on and be secured to the equivalent of a 2-inch by 10-inch by 10-inch wooden base.
Note: A 1 1/8-inch by 10-inch by 10-inch piece of exterior grade plywood may be used in lieu of the wooden base mentioned above.
(4) Platform planks shall not be placed on guardrails to obtain greater height.
(5) Metal scaffolds shall be securely tied to the building or structure by means of a double looped No. 12 iron wire, or single looped No. 10 iron wire or equivalent at intervals not to exceed 30 feet horizontally and subject to the following:
(A) Ties shall be required at the free ends of the scaffold when the height of the scaffold platform exceeds 3 times the least base dimension. The remaining ties of the first row shall be required when the height of the scaffold platform is four times the least base dimensions.
(B) Ties for subsequent levels shall be installed at 26-foot intervals vertically, with the last tie no further from the top than four times the least base dimension.
(C) As an alternate means, scaffolds shall be guyed or outriggers shall be used to prevent tipping or upsetting.
(D) Wind Loading. When scaffolds are partially or fully enclosed, specific precautions shall be taken to assure the frequency and adequacy of ties attaching the scaffolding to the building.
(6) Securely attached railings as provided by the scaffold manufacturer, or other material equivalent in strength to the standard 2- by 4-inch wood railing made from "selected lumber" (see definition), shall be installed on open sides and ends of work platforms 7 1/2 feet or more above grade. The top rail shall be located at a height of not less than 42 inches nor more than 45 inches measured from the upper surface of the top rail to the platform level. A midrail shall be provided approximately halfway between the top rail and the platform.
Note: Toeboards or side screens may also be required. (See Section 1621.)
(A) "X" bracing is acceptable as a toprail if the intersection of the "X" occurs at 45 inches (plus or minus 3 inches) above the work platform, provided a horizontal rail is installed as a midrail between 19 and 25 inches above the work platform. The maximum vertical distance between the "X" brace members at the uprights shall not exceed 48 inches.
(B) "X" bracing is acceptable as a midrail if the intersection of the "X" falls between 20 inches and 30 inches above the work platform.
Exceptions:
(1) Railings are not required on that side of bricklayers' and masons' scaffold adjacent to the work under construction provided the wall is higher than the adjacent work platform.
(2) For end rail openings less than 3 feet, double wrapped iron wire at least No. 12 gauge in thickness, or wire rope at least 1/4 inch minimum diameter is permitted, provided the wire or wire rope is securely fastened.
(7) Platform planks shall be of 2-inch by 10-inch or wider material and of such length that they overlap the ledgers at each end by at least 6 inches.
A plank shall not overlap an unsupported end of another plank.
The working platform shall cover the entire space between scaffold uprights, except for the open area under the back railing. Such open area shall not exceed 10 inches in width.
The inboard edge of the work platform shall be no more than 16 inches from the building or structure wall except for those scaffolds used by bricklayers and stonemasons the platforms of which shall extend to within 7 inches of the finish face of the building or structure on which the work is being performed.
(8) All ladders used for access shall conform to ladders, Article 25. When only a part of the width of the metal scaffold frame conforms to ladder spacing, then these frames must be erected in a manner that makes a continuous ladder bottom to top, with ladder sides of the frames in a vertical line.
(b) Tube and Coupler Scaffolds.
(1) A light duty tube and coupler scaffold shall have all posts, ledgers, ribbons and bracing of nominal 2-inch O. D. steel tubing. The posts shall be spaced no more than 6 feet apart by 10 feet along the length of the scaffold. Other structural metals when used must be designed to carry an equivalent load. No dissimilar metals shall be used together.
(2) A medium duty tube and coupler scaffold shall have all posts, ribbons and bracing of nominal 2-inch O. D. steel tubing. Posts spaced not more than 6 feet apart by 8 feet along the length of the scaffold shall have ledgers of nominal 2 1/2-inch O. D. steel tubing. Posts spaced not more than 5 feet apart by 8 feet along the length of the scaffold shall have ledgers of nominal 2-inch O. D. steel tubing. Other structural metals, when used, must be designed to carry an equivalent load. No dissimilar metals shall be used together.
(3) A heavy duty tube and coupler scaffold shall have posts, ribbons, and bracing of nominal 2-inch O. D. steel tubing, with the posts spaced not more than 6 feet by 6 feet 6 inches. Other structural metals, when used, must be designed to carry an equivalent load. No dissimilar metals shall be used together.
(4) Tube and coupler scaffolds shall be limited in heights and working levels to those permitted in Tables 1, 2, and 3. Drawings and specifications of all tube and coupler scaffolds above the limitations in Tables 1, 2, and 3 shall be designed by a Civil Engineer currently registered in the State of California.
(5) All tube and coupler scaffolds shall be constructed and erected to support 4 times the maximum intended loads as set forth in Tables 1, 2, and 3, or as set forth in the specifications by a Civil Engineer currently registered in California.
Table 1
Table 2
Table 3
(6) Posts shall be accurately spaced, erected on suitable bases, and maintained plumb.
(7) Ribbons shall be erected along the length of the scaffold, located on both the inside and the outside posts at even height. Ribbons shall be interlocked to the inside and the outside posts at even heights. Ribbons shall be interlocked to form continuous lengths and coupled to each post. The bottom ribbons shall be located as close to the base as possible. Ribbons shall be placed not more than 6 feet 6 inches on centers.
(8) Ledgers shall be installed transversely between posts and shall be securely coupled to the posts bearing on the ribbon coupler. When coupled directly to the ribbons, the coupler must be kept as close to the posts as possible.
(9) Ledgers shall be at least 4 inches but not more than 12 inches longer than the post spacing or ribbon spacing.
(10) Cross bracing shall be installed across the width of the scaffold at least every third set of posts horizontally and every fourth ribbon vertically. Such bracing shall extend diagonally from the inner and outer ribbons upward to the next outer and inner ribbons.
(11) Longitudinal diagonal bracing on the inner and outer rows of poles shall be installed at approximately a 45 degree angle from near the base of the first outer post upward to the extreme top of the scaffold. Where the longitudinal length of the scaffold permits, such bracing shall be duplicated beginning at every fifth post. In a similar manner, longitudinal diagonal bracing shall also be installed from the last post extending back and upward toward the first post. Where conditions preclude the attachment of this bracing to the posts, it may be attached to the ribbons.
(c) Tubular Welded Frame Scaffolds.
(1) Metal tubular frame scaffolds, including accessories such as braces, brackets, trusses, screw legs, ladders, etc., shall be designed, constructed, and erected to safely support four times the maximum rated load. The scaffold manufacturer's erection instructions shall be followed on all installations.
(2) Spacing of panels or frames shall be consistent with the loads imposed.
(3) Panels or frames shall be braced by horizontal bracing, cross bracing, diagonal bracing or any combination thereof for securing vertical members together laterally, and the cross braces shall be of such length as will automatically square and align vertical members so that the erected scaffold is always plumb, square, and rigid. All brace connections shall be made secure.
(4) Panel or frame legs shall be set on adjustable bases or plain bases placed on mud sills or other foundations adequate to support the maximum anticipated load.
(5) Panels or frames shall be placed one on top of the other with coupling or stacking pins to provide proper vertical alignment of the legs.
Note: Where an intervening ledge prevents the vertical stacking of legs, the ledge may be used as a base provided that an equally safe installation is obtained.
(6) Where uplift may occur, panels shall be locked together vertically by pins or other equivalent suitable means.
(7) Drawings and specifications for all frame scaffolds over 125 feet in height above the base plates shall be designed by a Civil Engineer currently registered in California.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
s 1645. Outrigger and Bracket Scaffolds.
(a) Heavy Trades.
(1) Outrigger beams of outrigger scaffolds for use by bricklayers, stonemasons, or other heavy trades shall be made of "selected lumber," or better. Those of the following sizes shall not project more than 6 feet beyond the outer support; shall be securely anchored and braced to prevent tipping or turning; and shall be spaced at centers of 7 feet 6 inches, or closer.
The inboard end of outrigger beams, measured from the fulcrum point to anchorage point, shall not be less than 1 1/2 times the outboard end in length. The fulcrum point of the beam shall rest on a secure bearing at least 6 inches square.
(2) On continuous scaffolds, where the beams may receive load from work platforms on each side, such beams shall not be less than 3 inches by 16 inches in cross section. For single scaffolds, consisting of a platform between 2 beams, the outrigger beams may have a smaller cross section, but not less than 3 inches by 12 inches. The platforms shall consist of planks, at least 2 inches by 10 inches, covering the full width of the projection. Planking shall be nailed or bolted or otherwise secured to outriggers.
The ends of the planks shall not project more than 18 inches beyond the outrigger, and not less than 6 inches, unless they are nailed in place. Every outrigger scaffold 7 1/2 feet or more in height shall be provided with a railing and toeboard. The top rail shall consist of double 2-inch by 4-inch members. One member shall be fastened in a flat position on top of the posts and the other member shall be fastened in an edge-up position to the inside of the posts and at the side of the top rail.
Additional protection in the form of screen enclosing the opening between rail and toeboard shall be provided if material on the scaffold is piled higher than the toeboard.
(3) Where additional working levels are required to be supported by the outrigger method, the plans and specifications of the outrigger and scaffolding structure shall be prepared by a Civil Engineer currently registered in California.
(b) Figure Four or Light Outrigger Scaffolds. (See Plate B-22, Appendix.) Figure Four or light outrigger frames shall be spaced not more than 10 feet apart, and shall be constructed as follows from sound lumber:
The outrigger ledger shall consist of 2 pieces of 1-inch by 6-inch or heavier material nailed on opposite sides of the vertical and angle braces. Ledgers shall project not more than 3 feet 6 inches from the outside wall line and shall be substantially braced and secured to prevent tipping or turning. The knee or angle brace shall intersect the beam at least 3 feet from the wall at an angle of 45 degrees, and the lower end shall be nailed to a vertical brace near the point where it contacts the wall. The platform shall consist of 2 or more 2-inch by 10-inch planks, which shall be of such length that they extend at least 6 inches beyond ledgers at each end. Unsupported projecting ends of planks shall be limited to an overhang of 18 inches, or less.
Each wooden bracket shall be hooked over a well-secured and adequately strong supporting member.
Every Figure Four or light outrigger scaffold 7 1/2 feet or more in height shall be provided with a railing and toeboard. The top rail shall consist of double 2-inch by 4-inch members. One member shall be fastened in a flat position on top of the posts and the other member shall be fastened in an edge-up position to the inside of the posts and at the side of the top member.
(c) Stud Jacks. (See Plate B-40, Appendix.) Stud-jack scaffold supports shall have ledgers of at least 2-inch by 6-inch materials, or equal, not longer than 5 feet, and each jack shall attach to notless than 2 sound, adequately fastened, 2-inch by 4-inch wall studs of normal length. Stud-jack scaffolds shall not be used at elevations of 7 1/2 feet or higher above the ground, unless so designed that a substantial backrail may be easily attached. (continued)