1-30. Structural Engineering Detailing Office Tutorial - Erection- 30

Structural steel assembly.

(a) Structural stability shall be maintained at all times during the erection process.

(b) The following additional requirements shall apply for multi-story structures:

(c) The permanent floors shall be installed as the erection of structural members progresses, and there shall be not more than eight stories between the erection floor and the upper-most permanent floor, except where the structural integrity is maintained as a result of the design.

(d) At no time shall there be more than four floors or 48 feet (14.6 m), whichever is less, of unfinished bolting or welding above the foundation or uppermost permanently secured floor, except where the structural integrity is maintained as a result of the design.

(e) A fully planked or decked floor or nets shall be maintained within 2 stories or 30 feet (9.1 m), whichever is less, directly under any erection work being performed.

(2) Plumbing-up. Connections of the equipment used in plumbing- up shall be properly secured.

Plumbing-up equipment shall be removed only with the approval of a competent person.

Members are checked for correctness line level and needed adjustments tumbuckles connected, temporary bracing connected

(3) Decking -- (1) Hoisting, landing and placing of deck bundles.

At the end of the shift or when environmental or jobsite conditions require, decking shall be secured against displacement.

(4) Roof and floor openings. Metal deck at roof and floor openings shall be installed as follows:

Where structural design and constructability allow, framed deck openings shall have structural members turned down to allow continuous deck installation.

(ii) Roof and floor openings shall be covered during the decking process. Where structural design does not allow openings to be covered, they shall be protected in accordance with Sec. 1926.760(a)(2).

(iii) Decking holes and openings shall not be cut until essential to the construction process, and openings shall be protected immediately in accordance with Sec. 1926.760(d) or be otherwise permanently filled.

(5) Space around columns. Wire mesh, exterior plywood, or equivalent, shall be used around columns where planks or decking do not fit tightly.

(6) Floor decking. Floor decking shall be laid tightly and secured to prevent accidental movement or displacement.

(7) Derrick floors. (i) A derrick floor shall be fully decked and/ or planked and the steel member connections completed to support the intended floor loading.

(ii) Temporary loads placed on a derrick floor shall be distributed over the underlying support members so as to prevent local overloading of the deck material.

Scaffold Standards & net standards maintained

(8) Man lock holes and safety holes as per project standard maintained other than bolt or galvanization holes

Edge protection and safety net holes maintained

Erection Sequence

Erection sequence is maintained through Erection drawing Contract numbers, Marks & Orientation and Phases.

Multi-Storey erected by a process called lift or cake splice

Erection begins with levelling floor and structural levels and, north settings, plant north and grid mark ups.

First, first column with tirfors temporary ties, than other coloum respective beams bracing etc erected. One stable box structure formed first.

Drawings

• Erection clearance of 2mm & 10mm maintained in model and drawings.

• All members should have Prelim mark and Orientation mark

• All members should be in erection plan & Reports

• All member should have fabrication drawing with title block mentioning revisions. the contract, special notes, field weld, phase, finish, special bolts and tightening methods.

• Proper plan elevation section view and deatail view covering all members should be in connection plan.

• Connection detail for all connection type should be present

• All Erecting length and elevation dimensions presented with grids and plant north or site north. having site map, interface or phase map

• Revisions clouds and revision properly shown

Detailing Standards The fabricator or manufacturer shall prepare and use detailing standards describing technical preferences and requirements. These standards shall show special information required on advance bills such as allowances for cuts, camber, or supplementary requirements. The detailing standards shall include how bills of material are prepared which, at a minimum, include:

(a) Sizes and quantities

(b) Appropriate specification references

(c) Special ordering information

(d) Any allowances or tolerances The detailing standards shall describe the fabricator’s or manufacturer’s methods of drawing layout, including, but not limited to:

(a) Sections and views.

(b) Title block information.

(c) The method of designating shipping sequences. (d) The piece marking system.

(e) Commonly used shop abbreviations.

(f) Fabricators: Showing bolt placement lists (including bolt type and installation requirements).

(g) Fabricators: Information required on weld symbols including any special NDT requirements.

(h) Manufacturers: If applicable, illustrate information to be included on weld symbols and the preferred way to designate surface preparation and coating requirements.

(i) Fabricators:

The detailing standards shall describe the method for

(i) Selection of connection type, connection geometry and connection material.

(ii) Detailing holes, fasteners, washers, cuts and copes.

(iii) Assignment of appropriate welding symbols (shop and field welds).

(iv) Selecting bolt installation method (for shop-installed bolts).

(v) Showing surface preparation (including specification of surface finish).

(vi) Designating coating requirements (including coating materials and dry film thickness).

(vii) Showing any necessary special instructions to fabricate and erect the steel.

Methods of Erection

Slinging method

• Dawson Shackle - Column

• LBG Swivel- Beam Erection

• and VLBG Load ring used

Access method

• Scaffold and MEWP used

Safety nets

• 22mm grip 1500 w flange/ 22 t

• 50mm Grip 200W/20mm

22 dia hole required at 1.6,spacings in bottom flange or base of web

Flooring

• Decking should be done with proper erection feasibility

• Gusset and plates should have weld access and 50 mm shelf angle decking placement

• the decking should have erection clearance angle between opposite beams, roughly distance of center to center - 1/2 maximum flange width.

• there should be proper decking grating span symbols and holes

finally snagging should be checked.

Column

(a) General requirements for erection stability. (1) All columns shall be anchored by a minimum of 4 anchor bolts. Each column anchor bolt assembly, including the welding of the column to the base plate, shall be designed to resist a 300 pound (136.2 kg) eccentric load located 18 inches (.46 m) from the column face in each direction at the top of the column shaft.

(2) Columns shall be set on level finished floors, pre-grouted leveling plates, leveling nuts, or shim packs which are adequate to transfer the construction loads.

(3) Unstable columns shall be evaluated by a competent person and be guyed or braced where deemed necessary.

(b) Repair, replacement or field modification.

(1) Anchor bolts shall not be repaired, replaced or field-modified without the approval of the project structural engineer of record.

(2) Such approval under paragraph (b)(1) of this section shall state whether the repair, replacement or modification has made guying or bracing of the column necessary.

(3) Prior to the erection of a column, the controlling contractor shall provide written notification to the steel erector if there has been any repair, replacement or modification of the anchor bolts of that column.

Beams and columns.

(a) General. During the final placing of solid web structural members, the load shall not be released from the hoisting line until the members are secured with at least two bolts per connection drawn up wrench-tight or the equivalent as specified by the project structural engineer of record, except as specified in paragraph (b) of this section.

Diagonal bracing.

Solid web structural members used as diagonal bracing shall be secured by at least one bolt per connection drawn up wrench-tight or the equivalent as specified by the project structural engineer of record.

(c) Double connections at columns and/or at beam webs over a column.

When two structural members on opposite sides of a column web, or a beam web over a column, share common connection holes, at least one bolt with its wrench-tight nut shall remain connected to the first member unless a shop-attached or field-bolted seat or similar connection device is present to secure the second member and prevent the column from being displaced. When seats are provided, the connection between the seat and the structural member that it supports shall be bolted together before the nuts are removed for the double connection.

(d) Column splices.

Each column splice shall be designed to resist a 300 pound (136.2 kg) eccentric load located 18 inches (.46 m) from the column face in each direction at the top of the column shaft.

(e) Perimeter columns.

Perimeter columns shall extend a minimum of 48 inches (1.2 m) above the finished floor to permit installation of perimeter safety cables prior to erection of the next tier except where structural design and constructability do not allow. (See appendix F to this subpart.)

(f) Perimeter safety cables. (1) Perimeter safety cables shall be installed at the perimeter during the structural steel assembly of multi-story structures.

(2) Perimeter safety cables shall consist of \1/2\-inch wire rope or equivalent installed at 42-45 inches above the finished floor and at the midpoint between the finished floor and the top cable.

(3) Holes or other devices shall be provided by the fabricator/supplier and shall be in or attached to perimeter columns at 42-45 inches above the finished floor and the midpoint between the finished floor and the top cable to permit installation of perimeter safety cables except where structural design and constructability allow.

(a) General. (1) In steel framing, where steel joists or steel joist girders are utilized and columns are not framed in at least two directions with solid web structural steel members, the steel joist or steel joist girder shall be field-bolted at or near columns to provide lateral stability to the column during erection.

(2) Where steel joists at or near columns span 60 feet (18.3 m) or less, the joist shall be designed with sufficient strength to allow one employee to release the hoisting cable without the need for erection bridging.

(3) Where steel joists at columns span more than 60 feet (18.3 m), the joists shall be set in tandem with all bridging installed unless an alternative method of erection, which provides equivalent stability to the steel joist, is designed by a qualified person and is included in the site-specific erection plan.

(4) A stabilizer plate shall be provided on each column for steel joists and steel joist girders and shall extend at least 3 inches (76 mm) below the bottom chord of the joist with a 13/16 inch (21 mm) hole to provide an attachment point for guying or plumbing cables.

(5) Bottom chords of steel joist girders and steel joists required by paragraph (a)(1) of this section shall be stabilized to prevent rotation during erection.

(6) A steel joist shall not be placed on any support structure unless such structure is stabilized.

(7) When steel joist(s) are landed on a structure, they shall be secured to prevent unintentional displacement prior to installation.

(8) Except for steel joists that have been pre-assembled into panels, connections of individual steel joists to steel structures in bays of 40 feet (12.2 m) or more shall be fabricated to allow for field bolting during erection.

(9) A bridging terminus point shall be established before bridging is installed. (See appendix C to this subpart.)

(10) Steel joists and steel joist girders shall not be used as anchorage points for a fall arrest system unless written direction to do so is obtained from a qualified person.

(11) No modification that affects the strength of a steel joist shall be made without the approval of the project structural engineer of record.

(b) Attachment of steel joists and steel joist girders. (1) Each end of "K" series steel joists shall be attached to the support structure with a minimum of two \1/8\-inch (3 mm) fillet welds 1 inch (25 mm) long or with two \1/2\-inch (13 mm) bolts, or the equivalent.

(2) Each end of "LH" and "DLH" series steel joists and steel joist girders shall be attached to the support structure with a minimum of two \1/4\-inch (6 mm) fillet welds 2 inches (51 mm) long, or with two \3/4\-inch (19 mm) bolts, or the equivalent.

(3) Except as provided in paragraph (b)(4) of this section, each steel joist shall be attached to the support structure, at least at one end, immediately upon placement in the final erection position and before additional joists are placed.

(4) Steel joists that have been pre-assembled into panels through the installation of bridging shall be attached to the structure at each corner before the hoisting cables are released.

(c) Erection of steel joists. (1) One end of each steel joist shall be attached to the support structure before an employee is allowed on the steel joist.

(2) On steel joists that span 40 feet (12.2 m) or less and that do not require erection bridging per Tables A and B, only one employee shall be allowed on the joist until all bridging is installed and anchored.

(3) Employees shall not be allowed on steel joists that span more than 40 feet except in accordance with Sec. 1926.757(d).

(4) When permanent bridging terminus points cannot be used during erection, additional temporary bridging terminus points are required to provide stability. (See appendix C of this subpart.)

(d) Erection bridging. (1) Where the span of the steel joist is equal to or greater than the span shown in Tables A and B, or in bays of 40 feet (12.2 m) through 60 feet (18.3 m), the following shall apply:

(i) The row of erection bridging nearest the midspan of the steel joist shall be bolted diagonal bridging;

(ii) Hoisting cables shall not be released until this bolted diagonal erection bridging is installed; and

(iii) No more than one employee shall be allowed on these spans until all other bridging is installed and anchored.

(2) Where the span of the steel joist is over 60 feet (18.3 m) through 100 feet (30.5 m), the following shall apply:

(i) The two rows of erection bridging nearest the third points of the steel joist shall be bolted diagonal bridging;

(ii) Hoisting cables shall not be released until this bolted diagonal erection bridging is installed; and

(iii) No more than two employees shall be allowed on these spans until all other bridging is installed and anchored.

(3) Where the span of the steel joist is over 100 feet (30.5 m) through 144 feet (43.9 m), the following shall apply:

(i) All rows of bridging shall be bolted diagonal bridging;

(ii) Hoisting cables shall not be released until all bridging is installed; and

(iii) No more than two employees shall be allowed on these spans until all bridging is installed.

(4) For steel members spanning over 144 feet (43.9 m), the erection methods used shall be in accordance with Sec. 1926.756.

(5) Where any steel joist specified in paragraphs (c)(2) and (d)(1), (d)(2), and (d)(3) of this section is a bottom chord bearing joist, a row of bolted diagonal bridging shall be provided near the support(s). This bridging shall be installed before the hoisting cable(s) is released.

(6) When bolted diagonal erection bridging is required by this section, the following shall apply:

(i) The bridging shall be indicated on the erection drawing;

(ii) The erection drawing shall be the exclusive indicator of the proper placement of this bridging;

(iii) Shop-installed bridging clips, or functional equivalents, shall be provided where the bridging bolts to the steel joists;

(iv) When two pieces of bridging are attached to the steel joist by a common bolt, the nut that secures the first piece of bridging shall not be removed from the bolt for the attachment of the second; and

(v) Bridging attachments shall not protrude above the top chord of the steel joist.

ERECTION PLAN (Erectors)

The erector shall prepare an erection plan for every project. The erection plan, in whole or in part, may be described graphically or in text. The erection plan shall include the following information as appropriate for the project:

(a) Project name and location.

(b) Indication of access for material delivery and equipment delivery, including lay-down, shake-out, and field-assembly areas.

(c) Sequence of erection.

(d) Dimensions and locations of cranes or other lifting equipment.

(e) Required site conditions for the crane location and confirmation of adequate base support for the crane.

(f) Sizes, model names or numbers, and capacity charts for lifting equipment. (g) Information regarding the heaviest lift and its radius; the longest radius and its lift weight; and the boom configuration for each at every location of the lifting equipment.

(h) Indicate critical lifts, if any, and include the critical lift protocol or procedure. (i) Requirements for multi-lift rigging.

(j) Types of slings to be used and, if more than one type, the locations in which they will be used.

(k) Rigging information for atypical lifts (weight, geometry, center of gravity, etc.) such as slings and hardware, rated lifting beams, beam clamps (including catalog cuts), as applicable to the lift.

(l) Designation of crane paths from position to position, indicating load travel paths, swing restrictions, and personnel exclusion zones

(m) Designation of space required for field assembly prior to erection.

(n) Identification of special fastening sequences and/or methods.

(o) Identification of special or atypical connections.

(p) Traffic control notes.

(q) Identification of specification requirements for erection, such as plumbing tolerances smaller than those stipulated in the Code of Standard Practice.

(r) The stability of the structure and individual members during erection shall be checked in accordance with Section 7.10.3 of the Code of Standard Practice. (s) Falsework requirements and corresponding design calculations.

(t) Jacking layout and jacking procedure.

(u) Notation of special problems due to overhead restrictions, underground utilities, barriers to crane tail swing, etc. The erection plan shall be reviewed before the start of erection by the erector’s project management team and be available to all employees assigned to the project. All revisions shall be approved by the site superintendent and communicated to

The safety plan described in Section 5.21 is an integral component of safety training.

OSHA provides minimum requirements for training in the following Subparts:

(a) General Safety and Health Provisions (OSHA Subpart C)

(b) Occupational Health and Environmental Controls (OSHA Subpart D)

(c) Hazard Communication

(d) Personal Protective and Life-Saving Equipment (OSHA Subpart E)

(e) Respiratory protection

(f) Fire Protection and Prevention (OSHA Subpart F)

(g) Signs, Signals and Barricades (OSHA Subpart G)

(h) Tools—Hand and Power (OSHA Subpart I)

(i) Welding and Cutting (OSHA Subpart J)

(j) Electrical (OSHA Subpart K)

(k) Scaffolding (OSHA Subpart L)

(l) Fall Protection (OSHA Subpart M) (m) Motor Vehicles, Mechanized Equipment and Marine Operations (OSHA Subpart O)

(n) Steel Erection (OSHA Subpart R)

(o) Connector Training

(p) Multiple Lift Rigging Training

(q) Stairways and Ladders (OSHA Subpart X)

(r) Toxic and Hazardous Substances (OSHA Subpart Z)

(s) Cranes and Derricks in Construction (OSHA Subpart CC)

(t) Aerial lift Training

(u) Qualified Rigger Training

(v) Qualified Signal Person Training

(w) Certified Crane Operator Training

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Anchored bridging means that the steel joist bridging is connected to a bridging terminus point.

Bolted diagonal bridging means diagonal bridging which is bolted to a steel joist or joists.

Bridging clip means a device that is attached to the steel joist to allow the bolting of the bridging to the steel joist.

Bridging terminus point means a wall, beam, tandem joists (with all bridging installed and a horizontal truss in the plane of the top chord) or other element at an end or intermediate point(s) of a line of bridging that provides an anchor point for the steel joist bridging.

Choker means a wire rope or synthetic fiber rigging assembly that is used to attach a load to a hoisting device.

Clipped connection means the connection material on the end of a structural member intended for use in a double connection which has a notch at the bottom and/or top to allow the bolt(s) of the first member placed on the opposite side of the central member to remain in place. The notch(es) fits around the nut or bolt head of the opposing member to allow the second member to be bolted up without removing the bolt(s) holding the first member.

Cold formed joist means an open web joist fabricated with cold formed steel components.

Cold forming means the process of using press brakes, rolls, or other methods to shape steel into desired cross sections at room temperature.

Competent person (also defined in Sec. 1926.32) means one who is capable of identifying existing and predictable hazards in the surroundings or working conditions which are unsanitary, hazardous, or dangerous to employees, and who has authorization to take prompt corrective measures to eliminate them.

Composite joists means steel joists designed to act in composite action with concrete floor and/or concrete roof slabs. Typically, a portion of the top chord of the joist (or a lug or similar device attached to the top chord of the joist) is embedded in the concrete slab.

Connector means an employee who, working with hoisting equipment, is placing and connecting structural members and/or components.

Construction load for joist erection means any load other than the weight of the employee(s), the joists and the bridging bundle.

Controlled Decking Zone (CDZ) means an area in which certain work (e.g., initial installation and placement of metal deck) may take place without the use of guardrail systems, personal fall arrest systems or safety net systems and where access to the zone is controlled.

Controlled load lowering means lowering a load by means of a mechanical hoist drum device that allows a hoisted load to be lowered with maximum control using the gear train or hydraulic components of the hoist mechanism. Controlled load lowering requires the use of the hoist drive motor, rather than the load hoist brake, to lower the load.

Controlling contractor means a prime contractor, general contractor, construction manager or any other legal entity at the site who has, by contract with other parties, the overall responsibility for the project, its planning, quality and completion.

Critical lift means a lift that exceeds 75 percent of the rated capacity of the crane or derrick, or requires the use of more than one crane or derrick.

Decking hole means a gap or void more than 2 inches (5.1 cm) in its least dimension and less than 12 inches (30.5 cm) in its greatest dimension in a floor, roof or other walking/working surface. Pre-engineered holes in cellular decking are not included in this definition.

Derrick floor means an elevated floor of a building or structure that has been designated to receive hoisted pieces of steel prior to final placement.

Double connection means an attachment method where the connection point is intended for two pieces of steel which share common bolts on either side of a central piece.

Erection bridging means the bolted diagonal bridging that is required to be installed prior to releasing the hoisting cables from the steel joists.

Fall restraint (Positioning device) system means a body belt or body harness used to prevent an employee from free falling more than 24 inches (61 cm) and where self rescue can be assured. It consists of an anchorage, connectors, a body belt or harness and may include a lanyard, deceleration device, lifeline, or suitable combination of these.

Girt (in pre-engineered metal buildings) means a "Z" or "C" shaped member formed from sheet steel spanning between primary framing and supporting wall material.

Headache ball means a weighted hook that is used to attach loads to the hoist load line of the crane.

Hoisting equipment means commercially manufactured lifting equipment designed to lift and position a load of known weight to an erection location at some known elevation and horizontal distance from the equipment's center of rotation. "Hoisting equipment" includes but is not limited to cranes, derricks, tower cranes, barge-mounted derricks or cranes, gin poles and gantry hoist systems. A "come-a- long" (a mechanical device, usually consisting of a chain or cable attached at each end, that is used to facilitate movement of materials through leverage) is not considered "hoisting equipment."

Leading edge means the unprotected side and edge of a floor, roof, or formwork for a floor or other walking/working surface (such as deck) which changes location as additional floor, roof, decking or formwork sections are placed, formed or constructed.

Metal deck means a commercially manufactured, structural grade, cold rolled metal panel formed into a series of parallel ribs; for this subpart, this includes metal floor and roof decks, standing seam metal roofs, other metal roof systems and other products such as bar gratings, checker plate, expanded metal panels, and similar products. After installation and proper fastening, these decking materials serve a combination of functions including, but not limited to: a structural element designed in combination with the structure to resist, distribute and transfer loads, stiffen the structure and provide a diaphragm action; a walking/working surface; a form for concrete slabs; a support for roofing systems; and a finished floor or roof.

Multiple lift rigging means a rigging assembly manufactured by wire rope rigging suppliers that facilitates the attachment of up to five independent loads to the hoist rigging of a crane.

Opening means a gap or void 12 inches (30.5 cm) or more in its least dimension in a floor, roof or other walking/working surface. For the purposes of this subpart, skylights and smoke domes that do not meet the strength requirements of Sec. 1926.760(d)(1) shall be regarded as openings.

Permanent floor means a structurally completed floor at any level or elevation (including slab on grade).

Personal fall arrest system means a system used to arrest an employee in a fall from a working level. A personal fall arrest system consists of an anchorage, connectors, a body belt or body harness and may include a lanyard, deceleration device, lifeline, or suitable combination of these. (As of January 1, 1998, the use of a body belt for fall arrest is prohibited by subpart M of this part.)

Pre-engineered metal building means a field-assembled building system consisting of framing, roof and wall coverings, and generally made of steel. Typically, in a pre-engineered metal building, many of these components are cold-formed shapes. These individual parts are fabricated in one or more manufacturing facilities and shipped to the job site for assembly into the final structure. Engineering design of the system is normally the responsibility of the pre-engineered metal building manufacturer.

Project structural engineer of record means the registered, licensed professional responsible for the design of structural steel framing and whose seal appears on the structural contract documents.

Purlin (in pre-engineered metal buildings) means a "Z" or "C" shaped member formed from sheet steel spanning between primary framing and supporting roof material.

Qualified person (also defined in Sec. 1926.32) means one who, by possession of a recognized degree, certificate, or professional standing, or who by extensive knowledge, training, and experience, has successfully demonstrated the ability to solve or resolve problems relating to the subject matter, the work, or the project.

Safety deck attachment means an initial attachment that is used to secure an initially placed sheet of decking to keep proper alignment and bearing with structural support members.

Seat means a structural attachment mounted to a structural member beneath a connection point, designed to support an incoming member that is to be connected to the first member.

Shear connector means headed steel studs, steel bars, steel lugs, and similar devices which are attached to a structural member for the purpose of achieving composite action with concrete.

Steel erection means the erection of steel buildings, bridges and other structures, including the installation of steel flooring and roofing members and all planking and decking used during the process of erection.

Steel joist means an open web, secondary load-carrying member of 144 feet (43.9 m) or less suitable for the support of floors and roofs. This does not include structural steel trusses or cold-formed joists.

Steel joist girder means an open web, primary load-carrying member, designed by the manufacturer, suitable for the support of floors and roofs. This does not include structural steel trusses.

Steel truss means an open web member designed of structural steel components by the project structural engineer of record. For the purposes of this subpart, a steel truss is considered equivalent to a solid web structural member.

Unprotected sides and edges means any side or edge (except at entrances to points of access) of a walking/working surface, e.g., floor, roof, ramp or runway, where there is no wall or guardrail system at least 39 inches (1.0 m) high.

Sec. 1926.752 Site layout, site-specific erection plan and construction sequence.

(a) Approval to begin steel erection. Before authorizing the commencement of steel erection, the controlling contractor must provide the steel erector with the following written notifications:

(1) The concrete in the footings, piers and walls or the mortar in the masonry piers and walls has attained, on the basis of an appropriate ASTM standard test method of field-cured samples, either 75 percent of the intended minimum compressive design strength or sufficient strength to support loads imposed during steel erection.

(2) Any repairs, replacements and modifications to the anchor bolts were conducted in accordance with Sec. 1926.755(b).

(b) Site layout. The controlling contractor shall provide and maintain the site layout as follows:

(1) Adequate access roads into and through the site for the safe delivery and movement of derricks, cranes, trucks, other necessary equipment, and the material to be erected and means and methods for pedestrian and vehicular control; and

(2) A firm, properly graded, drained area, readily accessible to the work with adequate space for the safe storage of materials and the safe operation of the erector's equipment.

(c) Overhead protection. All hoisting operations in steel erection shall be pre-planned in accordance with Secs. 1926.753(b) and 1926.759 to ensure that no employee is required to be exposed to overhead hazards.

(d) Site-specific erection plan. Where employers elect, due to conditions specific to the site, to develop alternate means and methods that provide employee protection in accordance with Sec. 1926.753(a)(5), Sec. 1926.757(a)(3) or Sec. 1926.757(e)(4)(i), a site-specific erection plan shall be developed by a qualified person and be available at the work site. Guidelines for establishing a site-specific erection plan are contained in appendix A to this subpart.

AISC 207-16 Revised November 2017