Structural Steel Erection Best Practices
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C O M M E M O R AT I O N
James Jonathan (Smitty) Smith
The Steel Erection Safety Committee was formed as a result of an injury incident where two ironworkers were seriously injured and one ironworker, James Jonathan (Smitty) Smith, was killed while erecting steel. Committee members include representatives from industry, employers, the Ironworkers Union, and Alberta Workplace Health and Safety among others. The main purpose of the committee is to develop and communicate industry recommended practices for the safe erection of structural steel in the construction industry. This booklet fulfills that objective and is published to honour the memory of James Jonathan (Smitty) Smith. Committee Members include: Marc Bergeron (Vice-Chair), AB&S Steel Rob Calver, Alberta Ironworkers Apprenticeship and Training Plan George Chapman, TSE Steel Ltd. Ray Cislo, Alberta Human Resources and Employment: Workplace Health and Safety Dale Francis, Supreme Steel Darrell LaBoucan, Ironworkers’ Local Union No. 720 Jeff Norris, Alberta Ironworkers Apprenticeship and Training Plan Don Oborowsky (Chair), Waiward Steel Fabricators Ltd. Glenn O’Neill, Ironworkers’ Local Union No. 725 LaMar Seward (Special Advisor), SNC-Lavalin ATP Ken Zwicker, Brytex Building Systems Inc. Committee members have volunteered many hours to support development of this booklet. Special thanks to the team leaders for drafting materials and providing technical expertise and advice to the Chair—all of which made this booklet possible.
This project was developed under the umbrella of the Manufacturers’ Health & Safety Association (MHSA) to facilitate committee administration and financial management and to collect and disseminate the information provided by the committee. The MHSA is an industry leader in promoting wellness in the manufacturing workplace. Our mission is to achieve work site wellness and eliminate occupational injuries and illness in the manufacturing industry through education, training, advocacy and partnership. Our values are: • Integrity • Trust • Participation • Collaboration • Performance Excellence To order this booklet, or for more information, contact an Alberta MHSA office at www.mhsa.ab.ca or an ACSA office at www.acsa-safety.org. © 2006 Manufacturers’ Health & Safety Association. All rights reserved. Reproduction of this booklet is strictly prohibited without written permission. EDITION: APRIL 2006
The following organizations have endorsed this booklet:
Alberta Construction Association Alberta Construction Safety Association (www.acsa-safety.org) Alberta Metal Building Association Alberta Steel Fabricators Association Calgary Steel Fabricators Association Canadian Institute of Steel Construction Alberta Region (www.cisc-icca.ca) Canadian Welding Bureau (www.cwbweb.org) International Union of Operating Engineers Local No. 955 (www.iuoe955.com) Ironworker Provincial Apprenticeship Committee (www.tradesecrets.org) Ironworkers’ Local Union No. 720 (www.ironworkers720.com) Ironworkers’ Local Union No. 725 Manufacturers’ Health and Safety Association (www.mhsa.ab.ca)
Not all requirements under the OHS Act, Regulation, and Code are discussed in this booklet. This is not a definitive guide to the legislation and does not exempt readers from their responsibilities under applicable legislation. In case of inconsistency between this booklet and the Occupational Health and Safety legislation, the legislation will always prevail. Note: All drawings in this publication represent artist’s rendition of information only. Drawings and photographs are for general illustration purposes and may not represent the exact work site setting or be interpreted as actual depiction of the OHS Act, Regulation, and Code requirements. Not all possible options are represented by illustrations.
Table of Contents Introduction ................................................................................................. 5 1 Safety ..................................................................................................... 7 1.1 1.2 1.3 1.4 1.5 1.6
Health and Safety Management System/Program ........................ 7 Worker Site Orientation ................................................................................... 8 Personal Protective Equipment (PPE) ..................................................... 8 Lifting and Handling Loads ........................................................................... 9 Safe Work Plan Modifications ....................................................................... 9 Housekeeping ....................................................................................................... 9
2 Project Pre-Planning ........................................................................ 11 2.1 2.2 2.3 2.4 2.5
Project Owner/Manager’s Responsibility .......................................... 11 Design Engineer’s Responsibility ............................................................ 11 Prime Contractor’s Responsibility .......................................................... 12 Steel Fabricator’s Responsibility .............................................................. 13 Steel Erector’s Responsibility ..................................................................... 13
3 Site-Specific Erection Plan ............................................................. 15 4 Structural Steel Assembly .............................................................. 17 4.1
Installing Single Columns ........................................................................... 17
4.2
Installing Columns in a Frame .................................................................. 18
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4.3 4.4 4.5 4.6 4.7 4.8
4.9 4.10 4.11 4.12 4.13
Installing a Single Beam ............................................................................... 19 Installing a Single Joist .................................................................................. 20 Installing Joist in Pairs .................................................................................... 21 Installing Joists in Bundles .......................................................................... 22 Structural Stability ............................................................................................ 23 Walking/Working Surfaces ......................................................................... 23 4.8.1 Shear Connectors for Composite Design (e.g., Nelson Studs) ............................................................................ 23 4.8.2 Slip Resistance on Skeletal Steel Structures ............................ 23 Connections ........................................................................................................ 24 Bolting and Torquing ..................................................................................... 25 Field Welding ...................................................................................................... 25 Pre-Engineered Metal Building Systems ............................................ 25 Anchor Bolts (Anchor Rods) ...................................................................... 26
5 Hoisting and Rigging ....................................................................... 27 5.1 5.2
5.3 5.4 5.5
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Inspections ........................................................................................................... 27 Loading and Unloading of Steel ............................................................. 28 5.2.1 Loading Trailers .................................................................................. 28 5.2.2 Positioning Trailers ............................................................................ 29 5.2.3 Unloading Trailers ............................................................................. 29 5.2.4 Shaking Out Steel .............................................................................. 29 5.2.5 Use of Sorting Hooks ....................................................................... 30 Hoisting Operations ....................................................................................... 30 Critical Lifts ........................................................................................................... 31 Rigging .................................................................................................................... 32 5.5.1 Load Rating of Slings and Other Rigging ............................... 32 5.5.2 Load Rating Marking: Sling Standard ...................................... 32
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5.5.3 Rejection of Slings ............................................................................. 32 5.5.4 Multiple Lift Rigging ......................................................................... 33
6 Use of Aerial Work Platforms ......................................................... 35 7 Decking ............................................................................................... 37 7.1 7.2
Landing Decking Bundles on Joists ...................................................... 37 Roof and Floor Openings ............................................................................ 37
8 Fall Protection .................................................................................... 39 8.1 8.2
Overview ............................................................................................................... 39 Fall Protection Systems ................................................................................. 40 8.2.1 Control Zone ....................................................................................... 40 8.2.2 Travel Restraint Systems ................................................................. 41 8.2.3 Fall Arrest Systems ............................................................................. 41 8.2.4 Safety Nets ........................................................................................... 44
9 Working at Heights ........................................................................... 45 9.1 9.2
Overview ............................................................................................................... 45 Safeguards ............................................................................................................ 45 9.2.1 Covered Openings ............................................................................ 45 9.2.2 Guardrails ............................................................................................. 45 9.2.3 Protection From Falling Objects: Securing Loose Objects Aloft ........................................................ 46 9.2.4 Protection From Falling Objects Other Than Materials Being Hoisted .................................................................. 46
10 Tools ..................................................................................................... 47 10.1 10.2 10.3
Use of Hand Tools ........................................................................................... 47 Use of Power Tools ......................................................................................... 47 Cutting/Burning/Welding Operations ............................................... 48
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11 Training and Education ................................................................... 49 11.1 11.2
Certification ......................................................................................................... 49 Training Personnel ........................................................................................... 49 11.2.1 Fall Hazard Training ........................................................................ 49 11.2.2 Specialty Training Programs ....................................................... 50
Appendix A: Definitions ....................................................................... 51 Appendix B: Sample Fall Protection Plan ....................................... 53 Figures 1 2 3 4 5 6 7 8 9 10
Tie joist .................................................................................................................... 20 Rigging for joists in pairs .............................................................................. 22 Clipped connection ........................................................................................ 24 Typical 4 anchor bolt column setting.................................................. 26 Sorting hook ........................................................................................................ 30 Multiple lift rigging .......................................................................................... 33 Examples of typical aerial work platforms ........................................ 35 Travel restraint systems ................................................................................. 41 Clearance distance .......................................................................................... 42 Fall arrest systems ............................................................................................ 44
Table 1
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Components of the Site-Specific Erection Plan ............................ 16
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Introduction Those involved in the construction industry all have an important part to play in ensuring safe work practices. This booklet provides guidance and advice about how structural steel can be erected safely. Although the information is not inclusive, this booklet outlines industry accepted best practices to be considered and followed by: • Owners/developers • Engineers • Prime contractors • Employers • Fabricators/manufacturers • Ironworkers/metal building system erectors There are four key foundation elements to the information provided in this booklet and these elements are required to ensure worker safety during steel erection on every project. 1. Ironworkers are certified, competent, and qualified to perform the work involved. (The Ironworker Trade regulation outlines tasks that may only be performed by Journeymen or Apprentice Ironworkers, which are a “compulsory trade” under section 21 of Alberta’s Apprenticeship and Industry Training Act.)
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2. Employers develop and use a Health and Safety Management System/ Program that enables effective analysis of health and safety hazards at the work site and implements control measures to eliminate hazards. 3. Industry members are aware of and comply with Alberta’s Occupational Health and Safety (OHS) Act, OHS Regulation, and OHS Code. Many of the requirements of this legislation are identified throughout this booklet, which can be referenced for further information. 4. An erection plan is created for each project, in which safe work practices are considered and built into each stage of construction, from pre-planning to completion of erection. Every individual working in the steel industry must take responsibility for safe work practices, regardless of job title. It is not good enough to assume that safety is someone else’s responsibility. Safety is everyone’s responsibility.
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S e c t i o n
1
Safety 1.1 HEALTH AND SAFETY MANAGEMENT SYSTEM/PROGRAM
• The purpose of a Safety Management System is to identify, assess, and control workplace hazards. To be effective, the following components are essential: - analysis of health and safety hazards at the work site - control measures to eliminate or reduce risks from hazards - clearly stated company policy and management commitment - worker competency and training - an inspection program - emergency response planning, including arrangements in place to transport injured or ill workers from the work site [ OHS CODE SECTION 180] - incident investigation - program administration • There must be a clear directive that such a system/program is the shared responsibility of all the members of the program (e.g., contractors and workers). [ OHS CODE PART 2, HAZARD ASSESSMENT, ELIMINATION AND CONTROL ]
• Prior to starting work, all workers should attend a structural steel erection best practices review for the project. A review document should be understood and signed as accepted. S T RU C T U R A L S T E E L E R E C T I O N BEST PRAC TI C ES
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• Weekly safety meetings should be held and the prime contractor must be kept informed, in writing, about discussions and issues that may affect safe erection of steel (e.g., weather conditions [such as wind], access, site conditions). 1.2 WORKER SITE ORIENTATION
Prior to starting work, every worker must attend a site orientation to be informed of and become familiar with: • site rules and regulations • erection plan and procedures • equipment to be used • hazard assessment • work area and emergency procedures (including the rescue plan) • work areas of other trades and the need to communicate planned work activities to them when working in close proximity 1.3 PERSONAL PROTECTIVE EQUIPMENT (PPE) [ OHS CODE PART 18, PERSONAL PROTECTIVE EQUIPMENT ]
• Employers and workers must ensure that this equipment is used whenever a worker is exposed to the relevant hazard. • All PPE must comply with standards referenced in the OHS CODE. • Additional PPE is supplied as required for various tasks. • Hard hats should be worn reversed only if they are specifically designed and approved by the manufacturer for that purpose. • Pant legs and laces must be tied or taped to avoid tripping hazards.
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1.4 LIFTING AND HANDLING LOADS [ OHS CODE PART 14 ]
• Manual handling of loads or materials by workers should be minimized. • Employers must provide, where reasonably practicable, appropriate equipment to help workers lift, lower, push, pull, carry, handle, or transport heavy or awkward loads. 1.5 SAFE WORK PLAN MODIFICATIONS
• Ensure that the safe work plan for permanent work areas, which may include general conditions and activities prevalent in the workplace, can be modified for temporary work areas with site-specific conditions and activities. • Ensure that modifications to the plan are developed by qualified personnel; the modifications must be documented and then communicated and available to all on-site personnel. 1.6 HOUSEKEEPING [ OHS CODE PART 12, GENERAL SAFETY PRECAUTIONS ]
• Store all supplies, such as bolts, shims, dunnage and debris, in proper containers and set away from areas where they can pose tripping hazards. • Do not leave loose bolts and nuts lying on steel or on ground. • Perform ongoing cleanup as required. • Do not string hoses through high traffic areas or stairs. Instead, hang the hoses up to eliminate the hazard.
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S e c t i o n
2
Project Pre-Planning Pre-planning must consider the structure’s design and constructability as well as the application of various fall protection systems. Project pre-planning is the responsibility of the: • Project Owner/Manager • Design Engineer • Prime Contractor • Steel Fabricator • Steel Erector 2.1 PROJECT OWNER/MANAGER’S RESPONSIBILITY
The project owner/manager is: • A key player in the overall shared responsibility of public and worker safety. • Responsible for ensuring that all organizations involved in any erection project are fulfilling their safety responsibilities. 2.2 DESIGN ENGINEER’S RESPONSIBILITY
The design engineer is responsible for: • Ensuring that the structural design and integrity is consistent with the structure’s intended use and that the structure can be erected safely. • The foundation supporting the structure. • Considering the safety of both workers and the public. S T RU C T U R A L S T E E L E R E C T I O N BEST PRAC TI C ES
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• Considering the site-specific soil and atmospheric conditions. • Ensuring that a minimum of 4 anchor bolts are on each main structural column. [SEE FIGURE 4] 2.3 PRIME CONTRACTOR’S RESPONSIBILITY
Before erection starts, the prime contactor must provide the following information and communicate it to the steel erector: • Minimum strength of concrete footings, piers, walls, and masonry that the concrete has attained based on appropriate CSA standard test method of field-cured samples. (See the latest edition of the CANADIAN INSTITUTE OF STEEL CONSTRUCTION (CISC) “HANDBOOK OF STEEL CONSTRUCTION” OUTLINING THE CISC CODE OF STANDARD PRACTICE FOR STRUCTURAL STEEL; PART ONE: CSA STANDARD CAN/CSA S16-01 AND PART SEVEN: CISC CODE OF STANDARD PRACTICE.)
Concrete compressive strength must be a minimum 75% of the intended compressive strength to support loads imposed during steel erection. • Notice of any repair, replacement, or modification of the anchor bolts for a column (required before the column is erected) as well as documentation to confirm that the changes were done in accordance with CSA standards. • Site Layout Testing Requirements. (See the appropriate sections of the latest edition of the CANADIAN INSTITUTE OF STEEL CONSTRUCTION (CISC) “HANDBOOK OF STEEL CONSTRUCTION”.) The prime contractor must also provide and maintain: • An overall project schedule that includes coordinating the various building trades. • Adequate access roads into and through the site for the safe delivery and movement of equipment and workers.
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• A firm, properly graded, drained area that is readily accessible to the workers and with adequate space for the safe storage of materials and the safe operation of the steel erection equipment. 2.4 STEEL FABRICATOR’S RESPONSIBILITY
The steel fabricator is responsible for: • Providing detailed connection information to ensure that the structure can be safely erected. • Providing, where required, safety attachments or anchor points as outlined in project specification/design documents. 2.5 STEEL ERECTOR’S RESPONSIBILITY
The steel erector is responsible for: • Ensuring workers are adequately qualified, suitably trained, and with sufficient experience to safely perform the assigned work. • Informing the prime contractor about access needs to the site and specific work areas. • Pre-planning work activities to ensure that workers are not required to work under unsafe or suspended loads. If workers must work beneath a load (e.g., connectors), they must be informed about the danger. [ OHS CODE SECTION 69 ] • Developing site-specific work instructions and procedures that identify access and area needs. [ OHS CODE SECTIONS 7 TO 9 ] • Ensuring that requirements for moving loads over working areas are met. The steel erector and crane operator must comply with the general and specific requirements of lifting and handling loads. [ OHS CODE SECTION 69 ] • Ensuring the prime contractor has provided a report verifying concrete strength.
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SECTION 3
S e c t i o n
3
Site-Specific Erection Plan Prior to starting erection activities, every worker involved in the erection should review the site-specific erection plan. The site-specific erection plan includes: • A site-specific hazard assessment. [ OHS CODE SECTION 7 ] • Erection drawings and erection procedures for connecting the structural parts of a skeleton structure. [ OHS CODE SECTION 190 ] Erection drawings and erection procedures for connecting the structural parts of a skeleton structure must be: • Prepared and certified by a professional engineer. [ OHS CODE SECTION 190 ] • Contain the components as shown in Table 1. • Made available to and reviewed by all workers before work begins. [ OHS CODE SECTION 190, SKELETON STRUCTURES ]
These erection drawings and procedures must: • Show the sequence in which the structure is erected. • Show the horizontal and vertical placement of base structures and footings. • Ensure that the structure is stable during assembly, which may include the size and location of temporary bracing. • Ensure that any erection procedures that have been added or changed on-site have been prepared and certified by a professional engineer before they are used. • Include pertinent information from the manufacturer’s drawings and erection instructions, if provided. S T RU C T U R A L S T E E L E R E C T I O N BEST PRAC TI C ES
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Table 1 Components of the Site-Specific Erection Plan COMPONENT
CONTENT DESCRIPTION
Sequence of Erection
• Manufacturer/supplier must plan the loading of trucks according to the erection sequence as well as the storage space on-site. • Material deliveries, staging, and storage • Coordination with other building trades
Hoisting Equipment
• Description and placement of equipment
Site Preparation
• Prime contractor must ensure that firm and level ground conditions are provided.
Steel Erection Activities
• • • • • • •
Preparation of Fall Protection Plan
• Workers must: - Use a fall protection system. [ OHS CODE SECTION 139 ] - Be informed about the fall protection plan and the safe use of all the fall protection systems being used on site. [ OHS CODE SECTION 144 ] - Be trained in the use of the fall protection systems. Training is provided by associations such as MHSA and ACSA or other accredited courses such as those provided by the OSSA. • Employers must develop fall protection procedures in a fall protection plan. [ OHS CODE SECTION 143(1) ] • Fall protection plan must specify: [ OHS CODE SECTION 143(2) ] - Fall hazards - Fall protection system - Procedures used to install, maintain, inspect, use, and disassemble the systems according to the manufacturer’s recommendations - Description of rescue or emergency procedures (Note: Calling 911, while appropriate, is not in itself a sufficient rescue plan.) • Fall protection plan must be available at the work site before work with a risk of falling begins. [ OHS CODE SECTION 143(3) ] (See Appendix B: Sample Fall Protection Plan)
[ OHS CODE SECTION 143 ]
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Verify anchor bolt/rod placement Notification of repairs and modifications Identify all lifts, including critical lifts Erection of structural steel components Stability: temporary and permanent bracing and guying Plumbing Securing connections
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S e c t i o n
4
Structural Steel Assembly 4.1 INSTALLING SINGLE COLUMNS
• All main structural columns should be anchored by a minimum of 4 anchor bolts. [SEE FIGURE 4] • Columns should be set on levelling plates, levelling nuts, shim packs, or level finished floors for adequate transfer of construction loads. • Any repairs, replacements, or field modifications of anchor bolts must be performed by a competent person with the approval of a professional engineer. • Before erecting a column, the prime contractor should notify the steel erector if there has been any repair, replacement, or modification of the anchor bolts for that column. • Attach the column rigging through a bolt hole in the top of the column in the web or a beam clip. If column rigging cannot be attached to the column due to the shape of the column, then a choker may be used provided that a way to prevent the choker from sliding up the column is in place. • Signal the crane to lift column. Adjust the crane’s line (by signaling the operator) to remain above the column rigging (pick point) of the lift as the column is being raised. • Once the column is lifted off the ground and the crane has the complete weight, stop the lift until the load settles (if required). Once the load settles, proceed to signal the crane operator to move the column into position.
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• Lower the column: - Placing columns on anchor bolts. Watch for pinch points. Once the base plate of the column touches the shims, put the washers and nuts on the anchor bolts. Plumb the column by tightening the anchor bolts. OR - Placing columns onto a steel column or beam. Watch for pinch points. Once the base plate of the column touches the connection point, bolt down. Plumb the column by tightening the connection bolts. Use spud wrench/sleaver bars to guide the column into position. Use a minimum of 4 bolts to secure the column. • Release the weight of the column from the crane. • Before releasing the rigging, make sure column is secure on the anchor bolts. • Unstable columns must be guyed or braced as necessary. 4.2 INSTALLING COLUMNS IN A FRAME
• Note: Frames are often referred to as bents. • Space columns out on the ground and place beams, bracings, or frames between columns as shown in the structural drawings to make large frame. Attach lower or upper beam framing between the columns as required. Ensure that the crane capacity for the lift will not be exceeded. • Attach rigging to the frame. Ensure the rigging is set up to pick a balanced, level load through the placement of the choker(s), and that the member attached to the rigging has the capacity to support the total weight of the frame being lifted. Load may be rigged off level in order to suit its final placement angle. If this is required, use clamps or erection lugs to prevent the chokers from slipping or shifting during the lift. • Signal the crane operator to lift frame. Adjust the crane’s line (by signaling the operator) to remain above the rigging (pick point) of the lift as the frame is being raised. PAGE 18
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• Once the frame is lifted off the ground and the crane has the complete weight, stop the lift until the load settles (if required). Once the load settles, proceed to signal the crane operator to move the frame into position. • Lower the frame onto the anchor bolts. Watch for pinch points. • Once the base plate of the column touches the shims, put the washers and nuts on the anchor bolts. Plumb the frame by tightening the anchor bolts. • Release the weight of the frame from the crane. • Before releasing the rigging, make sure columns are secure on the anchor bolts. If required, install temporary bracing before releasing the rigging to ensure the structural integrity at all times. 4.3 INSTALLING A SINGLE BEAM
• Note: Beams include purlins and girts. • Attach rigging in centre of load using the appropriate choker. • Signal the crane operator to lift beam. Adjust the crane’s line (by signaling the operator) to remain above the rigging point of the lift as the beam is being raised. • Once the beam is lifted off the ground and the crane has the complete weight, stop the lift until the load settles (if required). Once the load settles, proceed to signal the crane operator to move the beam into position. • Attach beam to supporting structure using a sufficient number of bolts or sufficient amount of weld to ensure the structural integrity before weight of load is placed on the connection plates. • Ensure columns have sufficient lateral support before installing members, such as crane beams, girts, and outriggers, which could cause the column to be eccentrically loaded. • Once load line on the crane has no weight, check the structural stability of the member. If it’s secure, release choker from beam. If required, add additional temporary bracing to secure the member before releasing crane hoist. S T RU C T U R A L S T E E L E R E C T I O N BEST PRAC TI C ES
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4.4 INSTALLING A SINGLE JOIST
• Wherever possible, boxing or pairing the joists is the preferred erection method. [SEE SECTION 4.5] • Where steel joists are used and the columns are not framed in two directions, the steel tie joists should be field bolted at or near the column to provide lateral stability before the intermediate joists are erected. [SEE FIGURE 1] • The bottom cords of steel joists must be stabilized with bridging to prevent rotation during erection. Joists are laterally unstable without bridging. • Wherever possible, dress joists with bridging on the ground before they are erected. This provides a method of connecting each joist onto a stabilized structure as it is erected. • Attach rigging in centre of load using the appropriate Figure 1 Tie joist. choker(s). Tying back the safety latch on the hook is not allowed. Rigging that is similar to column rigging can be used to unhook the crane from ground or beam line, if required.
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• Signal the crane operator to lift joist. Adjust the crane’s line (by signaling the operator) to remain above the rigging point of the lift as the joist is being raised. • Once the joist is lifted off the ground and the crane has the complete weight, stop the lift until the load settles (if required). Once the load settles, proceed to signal the crane operator to move the joist into position. • Place joist seat on beam line or other supporting structure and connect bridging. • Once load line on the crane has no weight, check structural stability of the member. If it’s secure, release choker from joist. If required, add additional temporary bracing to secure the member before releasing crane hoist. • Joists may be temporarily placed without bolting or welding if the joist weight is bearing straight down (usually possible on short joists), which ensures that the joist will not fall or move off (also known as “rattle off”) the supporting structure due to weather or site conditions (e.g., wind or vibrations from equipment). 4.5 INSTALLING JOISTS IN PAIRS
• Using the crane, pick up the first joist at ground level and bolt on the proper bridging. • Unhook the joist in the vertical position on the ground with the weight of the joist resting against the bridging. • Pick up the second joist and bolt it to the bridging attached to the first joist. • Use two sets of rigging so that each joist is picked up with a separate choker, centred on the joist weight. [SEE FIGURE 2] • All the practices for installing a single joist apply for installing joist in pairs. [SEE SECTION 4.4]
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Figure 2 Rigging for joists in pairs.
4.6 INSTALLING JOISTS IN BUNDLES
• Before hoisting bundles, install tie joists as suggested in SECTION 4.4, INSTALLING A SINGLE JOIST.
• Attach the appropriate choker in centre of the load on each bundle of joists that is to be lifted. • Attach a tag line to each bundle, wherever possible. • Signal the crane to lift bundle. Adjust the crane’s line (by signaling the operator) to remain above the rigging points of the lifts for each joist bundle that is being raised. PAGE 22
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• As the joists are lifted off the ground and the crane takes the complete weight, stop the lift until the load settles (if required). Once the load has settled, proceed to signal the crane operator to move the joists into position. • Set bundle on supporting structure. • Provided that the tie joists have been installed, intermediate joists may be temporarily placed without bolting or welding if the joist weight is bearing straight down (usually possible on short joists). Ensure that the joists will not fall or move off (also known as “rattle off”) the supporting structure due to weather or site conditions (e.g., wind or vibrations from equipment). 4.7 STRUCTURAL STABILITY
• Ensure that structural stability is maintained at all times. • Construction loads must not be placed on any structural steel unless such framework is safely bolted, welded, or otherwise adequately secured. • When used, temporary bracing must be in place and properly installed in conjunction with the steel erection plan to ensure the stability of the structure. • Temporary bracing can be removed only with the approval of a competent person. 4.8 WALKING/WORKING SURFACES 4.8.1 SHEAR CONNECTORS FOR COMPOSITE DESIGN (E.G., NELSON STUDS)
• Avoid the use of shear connectors, where possible, that could create tripping hazards. 4.8.2 SLIP RESISTANCE ON SKELETAL STEEL STRUCTURES
• Workers should avoid, where possible, walking on the top surface of any coated structural steel member that is slipperier than normal primed steel. S T RU C T U R A L S T E E L E R E C T I O N BEST PRAC TI C ES
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4.9 CONNECTIONS
• During the final placing of solid web structural members, the load should not be released from the hoisting line until the member is secured with at least two bolts per connection, wrench tight. Secondary members must have one bolt wrench tight. • A competent person must determine whether more than two bolts are required to ensure stability of a connection. • Avoid the use of connections, where possible, to the top flanges of beams, joists, or beam attachments in which they project vertically from or horizontally across the top flange. • During erection, diagonal bracing must be secured by at least one bolt per connection, wrench tight, before releasing load. • If a seat or equivalent device is used, it must be sized to support the weight of the construction process. • Where two beams, framing from opposite sides of a supporting member, share the same bolts, a clipped connection should be used unless a seated connection is used to facilitate safe erection. [SEE FIGURE 3] Figure 3 Clipped connection. PAGE 24
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4.10 BOLTING AND TORQUING
• • • • • • •
Follow the bolting instructions in the erection plan. Use retaining rings on impact sockets. Secure area below with flagging or signage where required. Inspect bolt bags daily for damage. Tie off impact wrench. Do not leave unsecured objects (e.g., bolt bags, tools, loose steel) at elevations. No more than four floors of unfinished bolting should be allowed above the uppermost finished floor.
4.11 FIELD WELDING
• Welders must be certified, competent, and qualified to perform the work involved. (The Welders Trade regulation outlines tasks that may only be performed by Journeymen or Apprentice Welders, which are a “compulsory trade” under section 21 of Alberta’s Apprenticeship and Industry Training Act.) • Welders must be employed by a company that is certified by the Canadian Welding Bureau (CWB) to CSA Standard W47.1. The company must have CWB Welding Procedure Specifications and Data Sheets available on site. • All welding must be performed by a person who is qualified by the CWB to CSA Standard W47.1 and who possesses the appropriate Performance Qualification card for the processes and positions in use. 4.12 PRE-ENGINEERED METAL BUILDING SYSTEMS
• Pre-engineered metal building systems often use steel members (such as tapered wide flange sections and coldformed purlins and girts) that may require a different erection process than conventional steel. • The metal building erector must have a site-specific erection plan as outlined in Section 3.
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4.13 ANCHOR BOLTS (ANCHOR RODS)
NOTE: The term “anchor bolt” is commonly used; however, the Canadian Standards Association standard CSA-S16 now uses the term “anchor rod.” • A minimum of 4 anchor bolts are important on main structural columns to ensure stability during erection, although it may not be a design requirement to support the completed structure. • Wherever possible, the 4 bolt anchor pattern should be symmetrical. • This type of anchor bolt is manufactured by the steel fabricator using rod specified by the design engineer (e.g., A307, 44W). The specifications must include the diameter, embedment, and hook length of the anchor bolt.
Figure 4 Typical 4 anchor bolt column setting.
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SECTION 4
S e c t i o n
5
Hoisting and Rigging 5.1 INSPECTIONS
• Careful consideration must be given to the ground conditions and the soil compaction in areas in which cranes are to be moved and operated. • If work is done or equipment is operated in the area of an energized overhead power line, the employer must contact the power line operator to determine the voltage of the power line, which determines the safe approach distance. Until the power line operator verifies the voltage, the employer must maintain a safe clearance distance according to OHS CODE PART 17. • For lattice boom cranes, assemble the boom sections precisely according to the manufacturer’s recommendations to attain the boom strength on which the capacities in the load chart are based. • On cranes operating with outriggers, the beams must be extended with the pads down according to manufacturer’s recommendations. The ground should be checked periodically for settling, and the outriggers reset if necessary. • If a crane makes its lift on rubber (without outriggers), ensure that the tires are properly inflated; otherwise, the capacity and crane stability will be reduced. Check the ground periodically for settling. • Always use outrigger mats or pads to provide additional support for the crane. In unstable surface conditions, cribbing may be needed, which should be tightly spaced using rigid timbers.
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• Due to side loading in the boom, cranes should be level within the manufacturer’s specifications. • When using crawler cranes, the tracks can be extended or retracted (use the appropriate chart). Ensure firm, level footing under the entire crane area. • The crane operator must perform a visual inspection of all the crane components required to operate the crane in a safe condition. • Ensure the load does not strike the boom or outriggers and never allow a crane boom to hit or touch any structure. 5.2 LOADING AND UNLOADING OF STEEL
• Workers must stay out of the danger zone created by moving equipment or loads to prevent being struck. [ OHS CODE SECTION 258 ] If workers are in danger due to the movement of a load being lifted, a tag line must be used to control the load. [ OHS CODE SECTION 70 ] • All goods, materials, and equipment at work sites must be stacked, stored, and secured in such a way that they do not flow, move, roll, or collapse. • Workers responsible for stacking, storing, or securing goods, materials, and equipment must be trained in the safe methods for doing so. [ OHS CODE SECTION 189; OHS REGULATION SECTION 15 ]
5.2.1 LOADING TRAILERS
• Use adequate dunnage between steel layers to ensure load remains level and to provide safe access to the load. • Loads transported on trailers and vehicles must be secured according to the Cargo Securement Regulation, Alberta Regulation 1/2005–Traffic Safety Act (www.inftra.gov.ab.ca/legislation.htm). This regulation adopts the standard jointly developed by the Canadian Council of Motor Transport Administrators (CCMTA) and the USA Commercial Vehicle Safety Alliance (CVSA). For information, visit www.ccmta.ca.
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5.2.2 POSITIONING TRAILERS
• Inspect potential trailer spotting locations. • Whenever possible, position trailers at site locations that have been packed and travelled, indicating that the soil can accommodate the weight. • Use appropriate dolly pads with all trailers to distribute the load. 5.2.3 UNLOADING TRAILERS [ OHS CODE SECTION 189 ]
• The steel lay-down area should be clearly identified. • Loads are strapped during shipping and relocation. Before unloading, check whether the load has shifted in any way. • Check loads for loose or dangerous pieces before un-strapping. • When a forklift cannot be used effectively, use hoisting equipment to unload trailers. • Loads should be landed on a solid base or dunnage to minimize the potential for unexpected movement when weight comes off the hooks. • Use a flag person at all vehicle/pedestrian traffic areas. • Designated signallers must be in constant communication with the equipment operator (visually or electronically). [ OHS CODE SECTION 191 ] 5.2.4 SHAKING OUT STEEL
• Use adequate dunnage between steel to give enough clearance and stability for hooking up activities. • Keep hands and all body parts clear of pinch points and crush areas. • Avoid walking on or between beams in the lay-down area. • Stay clear of loads. • Use tag lines on hard-to-control loads. [ OHS CODE SECTION 70 ] • Use appropriate footwear to suit ground conditions.
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5.2.5 USE OF SORTING HOOKS [ OHS CODE SECTION 303(3) ]
• Sorting hooks should not be used for erecting steel. • Sorting hooks may be used for off-loading and at ground level for shaking out steel that is bunched or improperly stacked. This helps avoid pinching hands, fingers, and legs. • Sorting hooks should not be used in conjunction with chokers. Figure 5 Sorting hook.
5.3 HOISTING OPERATIONS OHS CODE PART 6, CRANES, HOISTS AND LIFTING DEVICES
• Crane operators must be competent and qualified to perform the work involved. • Crane operator credentials should be verified prior to hoisting. • Only a certified crane and hoisting equipment operator can operate: - Mobile cranes rated at 15 tons or greater. - Boom trucks rated at 5 tons or greater. [ CRANE AND HOISTING OPERATOR TRADE REGULATIONS ]
• Crane certification should be verified and the crane must be visually inspected before each use.
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• Crane operator must verify the weights of pieces and materials to be lifted. Load capacities must be known, provided to the operator, and verified with work-related personnel. [ OHS CODE SECTION 68 ] • All crane components must be inspected and maintained in good condition. • Cranes must be set up on a firm and level surface suitable for the intended activities and according to the manufacturer’s recommendations. • Crane outrigger pads or cribbing should be used at all times. OHS CODE SECTION 69
• The planning for a lift must ensure that, wherever possible, a load is not moved over workers. OHS CODE PART 21, RIGGING
• Workers must inspect slings for damage and excessive wear before use; inspect slings regularly. • Use softeners as required. • Use only industry-recognized rigging practices. • Use of makeshift (non-manufactured, non-engineered) load bearing rigging components is prohibited. [ OHS CODE SECTION 304 ] • Assign tasks to apprentices based on skill and experience level. • Apprentices are to be under the direct supervision of a certified worker. 5.4 CRITICAL LIFTS
• The equipment and procedure used for every lift, including critical lifts, are part of the site-specific erection plan approved by a professional engineer. • A critical lift is a lift that exceeds 90% of the crane chart value, a lift that requires the use of more than one crane or derrick, or a lift in which the crane travels with a suspended load.
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5.5 RIGGING [ OHS CODE PART 21 ]
5.5.1 LOAD RATING OF SLINGS AND OTHER RIGGING [ OHS CODE SECTIONS 293, 304 ]
• The maximum load rating is not the breaking strength of the piece of rigging. An employer must ensure that the load rating of the piece of rigging is appropriate (5 to 1 for all below-the-hook lifting devices; 10 to 1 for hoisting of personnel). • The use of makeshift rigging fittings or attachments that bear a load is prohibited. [ OHS CODE SECTION 304 ] Load bearing rigging components must be manufactured or designed by a professional engineer, fabricated by an appropriately qualified and competent worker, and certified by a professional engineer. • The maximum load rating must be clearly marked on the rigging. If marking the rigging is not possible, the load rating should be available to workers on the site. 5.5.2 LOAD RATING MARKING: SLING STANDARD [ OHS CODE SECTIONS 293, 297, 298 ]
• Slings must meet the requirements of ASME Standard B30.9-1996, Slings. The standard describes technical requirements for construction, load rating, proof testing, identification, maintenance, environmental effects, end attachments, inspection, repair, and use. 5.5.3 REJECTION OF SLINGS [ OHS CODE SECTIONS 305, 306, 307 ]
• Slings must be checked before each use by workers. • Damaged slings must be permanently removed from service.
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5.5.4 MULTIPLE LIFT RIGGING
• Rigging components must be designed with a 5 to 1 safety factor. [ OHS CODE SECTION 292 ]
• A total load must not exceed the rated capacity of the hoisting or rigging equipment. • “Rigging assembly” must be rigged: - With the members attached at their centre of gravity and kept in a safe level position. - From the top down. - At least 2 m apart. • Special consideration should be given to the method of rigging steel with finished surfaces in order to avoid slipping.
Figure 6 Multiple lift rigging.
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Use of Aerial Work Platforms [ OHS CODE SECTIONS 346-347 ]
• Worker must inspect aerial work platforms before each use. • Operators must be trained to operate aerial work platforms. [ FOR EXAMPLE, A COURSE OFFERED BY ASSOCIATIONS SUCH AS MHSA AND ACSA OR OTHER ACCREDITED COURSES SUCH AS THOSE PROVIDED BY OSSA, E.G., AWP2005 – 17 ]
• Use of and loading of platforms must be in accordance with manufacturer’s specifications (e.g., travel with boom raised, hoisting of materials). • Ground should be level and firm.
Figure 6.1Examples Examples typical aerial work platforms. Figure 7 ofof typical aerial work platforms. S T RU C T U R A L S T E E L E R E C T I O N BEST PRAC TI C ES
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• Workers must not stand or climb on the mid rail or top rail of the aerial platform. Planks, ladders, or similar devices must not be used on the work platform to gain additional height. • Workers must not use aerial platforms as a material-hoisting device unless approved for this use by the manufacturer or certified by a professional engineer. • The work platform’s guardrail provides fall protection but a full body harness and lanyard must also be used if required by the manufacturer’s specifications for the platform. • When transferring from an aerial platform to a structure, workers must tie off to the structure before leaving the basket.
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7
Decking 7.1 LANDING DECKING BUNDLES ON JOISTS
• Do not use bundle packaging or strapping for hoisting unless specifically designed for that purpose. • Loose items on top of bundles must be secured to the bundles. • Land bundles on framing members so that the bundles are sufficiently supported to allow un-banding without dislodging the bundles. • At shift end, all decking must be secured against displacement. • No decking loads are allowed on steel joists until erector has confirmed that bridging is installed and anchored and all joist bearing ends are attached. 7.2 ROOF AND FLOOR OPENINGS [ OHS CODE SECTION 314 ]
• Metal decks must be installed to meet these requirements: - Roof and floor openings must be covered during the decking process. - All covers must be secured. - All covers must be marked with a warning sign or marking. - A hole in which any part of a worker can fall must be covered. - Holes and openings must not be cut until essential to the construction process. Holes and openings must be immediately protected. - Space around columns must be protected to prevent objects from falling onto the area or workers below. • Skylight openings must meet these same requirements. S T RU C T U R A L S T E E L E R E C T I O N BEST PRAC TI C ES
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Fall Protection [ OHS CODE SECTIONS 138 TO 161 ]
8.1 OVERVIEW
• Workers must use a fall protection system if they may fall 3 m or more, or if there is an unusual possibility of injury if a worker falls less than 3 m (e.g., falling onto exposed rebar pointing upward). • Workers working on flat roofs and workers engaged in connecting structural members of a skeleton structure are not exempt from using fall protection. • During an emergency response to rescue after a fall [ OHS CODE SECTION 143 ], it is not sufficient to call 911. After an arrested fall, the worker remains suspended in mid-air from the full body harness, awaiting rescue, and suspension trauma can start within minutes. OHS Code requires a written rescue procedure available to the workers before the work with a risk of falling starts. [ OHS CODE SECTION 143(2) ]
• A fall protection plan must specify the: - Fall hazards at the work site. - Fall protection system to be used at the work site. - Procedures used to assemble, maintain, inspect, use, and disassemble the fall protection system.
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- Rescue procedures to be used if a worker falls or is suspended by a personal fall arrest system or safety net and needs to be rescued. • Review fall protection plan, including the rescue plan, with workers. 8.2 FALL PROTECTION SYSTEMS [ OHS CODE SECTION 139(1) ]
• Four approaches are commonly used to protect workers from falling from a height: - A control zone is an area from an unguarded edge where workers are not allowed. - A travel restraint system prevents a worker from reaching an edge or work position from which the worker could fall. - A fall arrest system catches a falling worker in mid-air, safely bringing the worker to a complete stop and preventing the worker from hitting a lower surface. - A safety net catches a falling worker in mid-air. • If work aloft requires the use of both hands, and solid balance cannot be maintained, a work positioning system must be used. A work positioning system is as simple as two short lanyards connected from the full body harness’s side D-rings to the structure. A work positioning system is not a fall arrest system. While using a work positioning system, a worker must still have a fall arrest lanyard connected from the worker’s back D-ring to an anchorage located at shoulder level or preferably higher. 8.2.1 CONTROL ZONE
• A control zone is the area within 2 m of an unguarded edge of a level, elevated work surface. • If workers will always remain further from the unguarded edge than the width of the control zone (i.e., workers are not working in the control zone), no other fall protection system needs to be used. PAGE 40
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• Control zones cannot be used to protect workers from falling from a skeletal structure that is a work area. 8.2.2 TRAVEL RESTRAINT SYSTEMS
• Travel restraint systems are not intended to arrest a fall. These systems, which include guardrails and similar barriers, prevent a worker from reaching an edge or work position from which the worker could fall. • Self-retracting lifelines must not be used in a travel restraint system unless the length of the lifeline on the drum of the unit prevents the worker from reaching the edge or work position from which the worker could fall. If a worker approaches the edge and there is some lifeline still spooled on the drum, the worker could go past the edge and fall. 8.2.3 FALL ARREST SYSTEMS
• Use an aerial work platform, man basket, or 100% fall protection to access steel. • If using a ladder to access steel, ensure that the ladder is secured to the steel. [ OHS CODE SECTION 136 ] • Secure the work area as required with signage or control entry by groundman monitoring and granting access where needed. Figure 8 Travel restraint systems. S T RU C T U R A L S T E E L E R E C T I O N BEST PRAC TI C ES
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• Use aerial work platforms or man baskets as a work platform wherever possible where protecting against a fall is difficult. • Always anchor to a point as high as possible—shoulder height or higher is best. Doing so reduces the distance a worker falls, helps prevent contact with a lower surface, and reduces the force of the fall. • Be aware of the clearance distance required in a fall. Using a 1.8 m long lanyard, a worker needs at least 6.0 m of clear space below the level of the anchor point.
Assumptions: The worker is 1.8 m (6 ft.) tall using a 1.8 m (6 ft.) lanyard. The combined weight of the worker, clothing, and tool belt is at least 100 kg (220 lbs.).
A
Length of Lanyard (1.8 m [6 ft.])
B
1.1 m (3.5 ft.) due to shock absorber pulling apart
C
Harness stretch plus D-ring sliding (0.45 m [1.5 ft.])
D
Height of worker (1.8 m [6 ft.])
E
Safety Factor – clearance below feet (0.9 m [3 ft.])
F
A+B+C+D+E Overall minimum clearance required is 6.0 m (20 ft.)
Figure 9 Clearance distance.
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• Tying in to an anchor at foot level is dangerous. A CSA approved shock absorber will safely absorb energy based on a 2 m fall. But tying a 1.8 m lanyard at foot level can subject the shock absorber to a 4 m free fall. The shock absorber’s webbing may fully extend without absorbing all the energy of the fall, resulting in a “bounce” at the bottom. The remaining energy (and there could be a great deal of it) goes into the worker, potentially causing serious injury. • A personal fall arrest system is an active protection system that comes into service when a fall occurs. • A complete fall arrest system must consist of: - anchorage - connecting device (e.g., lanyard, retractable, shock absorber, lifeline, etc.) - full body harness - rescue plan and equipment • Anchor points used for attachment of a personal fall arrest system must be capable of supporting a load of at least 22.2 kilonewtons (5000 pounds-force) per worker attached, in any direction required to resist a fall. • If the structure to which the anchor point is attached is not able to withstand the 22.2 kilonewtons force, then the anchor point can be derated but must be designed by a professional engineer for this purpose. • Temporary horizontal lifeline systems must comply with OHS CODE SECTION 157. Also see CSA Standard Z259.13-04 Flexible horizontal lifeline systems.
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8.2.4 SAFETY NETS
• Safety nets must meet the requirements of the ANSI standard. [ OHS CODE SECTION 320 ] A professional engineer must certify that the supporting structure and the net system are strong enough for the load(s) likely to be experienced. • Safety nets for fall protection, both interior and on a perimeter of a building, can protect workers when other means are not practical. [ OHS CODE SECTION 320 ]
Figure 10 Fall arrest systems. PAGE 44
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9
Working at Heights 9.1 OVERVIEW • WEATHER AWARENESS. Foreman can exercise judgment and shut down all
work at his or her own discretion due to wind, rain, snow, or any other unusual weather condition. If this occurs, set up cables, ropes, or permanent barricades, complete with signage indicating the decision. • MATERIALS. Materials must be hoisted using material lifts or ropes and must be secured to prevent falling off steel. Do not carry materials up ladders. • TOOLS. Tools must be hoisted using material lifts or ropes and, when the tools are not in use, they must be secured to prevent falling off steel or from being removed. Do not carry tools up ladders unless the tools are part of a tool belt. 9.2 SAFEGUARDS 9.2.1 COVERED OPENINGS
• Secure and mark covers over open holes. [ OHS CODE SECTION 314 ] 9.2.2 GUARDRAILS
• Install handrails and kick-plates in conjunction with stair and grating erection, where required. [ OHS CODE SECTION 315 ] • Perimeter safety guardrail made with wire rope must consist of systems that comply with OHS CODE SECTION 315. S T RU C T U R A L S T E E L E R E C T I O N BEST PRAC TI C ES
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9.2.3 PROTECTION FROM FALLING OBJECTS: SECURING LOOSE OBJECTS ALOFT
• All materials, equipment, and tools that are not in use while aloft must be contained, restrained, or protected from falling. [ OHS CODE SECTION 189 ] 9.2.4 PROTECTION FROM FALLING OBJECTS OTHER THAN MATERIALS BEING HOISTED [ OHS CODE SECTION 318 ]
• Employers must protect workers from being struck by falling objects (e.g., an overhead safeguard strong enough to withstand the shock load of falling objects), or if workers enter into the danger area, then barricades, warning signs, horns, or flashing lights can warn workers of the hazard. • The prime contractor must prohibit other construction processes below steel erection unless overhead protection for the workers below is provided. • The prime contractor must ensure that all deck or floor openings, including openings in and around column penetrations, are covered or closed to prevent tripping or falling object hazards. • Safety nets can be used to protect workers from falling objects.
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Tools 10.1 USE OF HAND TOOLS
• • • •
Use all hand tools for the purpose intended by the manufacturer. Use the right tool for the right job. Inspect all tools for defects prior to use. Prevent all hand tools from falling (where applicable) by using items such as lanyards, netting, and chains.
10.2 USE OF POWER TOOLS [ OHS CODE PART 25 ]
• • • • •
Power tools must be used in accordance with manufacturer’s specifications. Inspect all power tools prior to use. Ensure all guards are in place. Take damaged tools out of service and tag them for repair. Use proper personal protective equipment (PPE) while operating power tools. • Ensure portable magnetic drills are tied off and equipped with lock-tight cord ends. • Prevent all power tools from falling (where applicable) by using items such as lanyards, netting, and chains.
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10.3 CUTTING/BURNING/WELDING OPERATIONS [ OHS CODE PART 10, FIRE AND EXPLOSION HAZARDS ]
• ABC 20 lb. fire extinguishers are required at hot work locations. • Secure compressed gas cylinders in an upright position and protect them or locate them away from falling objects. • Oxygen fuel systems require a flashback arrestor and a back-flow prevention device. [ OHS CODE SECTION 171(4) ] • A back-flow prevention device is unnecessary in the fuel line of single-line torch systems operating on fuel gas and aspirated ambient air, since the potential for creating an explosive or flammable gas mixture in the hose does not exist (e.g., tiger torch). • Remove combustible material from area, if possible. • Use fire blankets where required. • Assign a fire watch where required. • Ensure that welding services from vehicles comply with OHS CODE SECTIONS 172–174. [ OHS CODE PART 18, RESPIRATORY PROTECTIVE EQUIPMENT ]
• Workers exposed to an airborne contaminant or mixture of contaminants must wear appropriate respiratory protective equipment.
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1 1
Training and Education 11.1 CERTIFICATION
• It is a legal requirement that workers in steel erection projects be certified and competent in the work that they are assigned to do. • See Appendix A: Definitions. 11.2 TRAINING PERSONNEL
• Employers must ensure that workers are trained. [ OHS REGULATION SECTION 15 ] Subject to assessment and verification, workers trained by a previous employer do not need to be trained again in the same activities. If a worker has not received training, the employer must train the worker as required in the specific job-related requirements and the OHS Act, OHS Regulation, and OHS Code. • Technical or on-the-job training must be provided by competent personnel. • A worker who is provided with training must use the procedures appropriately and apply the training. 11.2.1 FALL HAZARD TRAINING
• Employers should provide a training program for all employees exposed to fall hazards. The program must include training and instruction in: - The fall protection requirements of the industry. - Safe use of the fall protection system(s) used at the work site. - The fall protection plan, including procedures if a worker falls and is suspended. S T RU C T U R A L S T E E L E R E C T I O N BEST PRAC TI C ES
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11.2.2 SPECIALTY TRAINING PROGRAMS
• Employers must provide employees with special training that identifies the nature of the hazards and the proper working techniques in: - multiple lift procedures - connection procedures - controlled decking zone procedures - special equipment and tools
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A p p e n d i x
A
Definitions TERM
DEFINITION
AITA
Alberta Apprenticeship and Industry Training Act (www.qp.gov.ab.ca/catalogue)
ACSA
Alberta Construction Safety Association (www.acsa-safety.org)
ASME
American Society of Mechanical Engineers
Certified Crane and Hoisting Equipment Operator
Person who holds a certificate issued under the Alberta Apprenticeship and Industry Training Act or holds an Interprovincial Standards “Red Seal”. (The Crane and Hoisting Equipment Operator Trade regulation outlines tasks that may only be performed by Journeymen or Apprentice Operators, which are a “compulsory trade” under section 21 of Alberta’s Apprenticeship and Industry Training Act.)
Certified Ironworker*
Person who holds a certificate issued under the Alberta Apprenticeship and Industry Training Act or holds an Interprovincial Standards “Red Seal”. *
Includes Ironworkers and Ironworkers-MBSE (Metal Building Systems Erector). Refer to the Trades Regulations for specific scope of duties.
Competent Worker
A worker who is adequately qualified, who is suitably trained and with sufficient experience to safely perform work without supervision or with only a minimal degree of supervision. [ OHS CODE SECTION 1 ]
Connector
An employee who, when working with hoisting equipment, is placing and connecting structural members or components.
Controlled Decking Zone (CDZ)
A control zone is an approach to fall protection that places special requirements on workers and work being performed on a level working surface within 4 m of an unguarded edge from which a worker could fall. [ OHS CODE SECTION 161 ]
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TERM
DEFINITION
Critical Lift
A lift that exceeds 90% of the crane chart value, a lift that requires the use of more than one crane or derrick, or a lift in which the crane travels with a suspended load.
Decking Hole
An opening or hole through which a worker can fall. As a guideline, such an opening or hole would be more than 50 mm in its least dimension and less than 300 mm in its greatest dimension. [ OHS CODE SECTION 314 ]
Decking Opening
An opening through which a worker can fall. As a guideline, such an opening means a gap or void 300 mm or more in its least dimension in a floor, roof, or other walking/working surface. [ OHS CODE SECTION 314 ]
OSSA
Oil Sands Safety Association (www.ossa-wb.ca)
Prime Contractor
An owner, contractor, construction manager, or any other legal entity at site who has the overall responsibility for the project, its planning, quality, and completion. The prime contractor is responsible for (1) establishing and maintaining a system or process that ensures compliance with the Occupational Health and Safety Act, Regulation and Code; and (2) ensuring that first aid services, equipment and supplies required by the Occupational Health and Safety Code are available at the work site.
Professional Engineer
Person who holds a certification of registration to engage in the practice of engineering, and is a member or Licensee in good standing of the Association of Professional Engineers, Geologists, an Geophysicists of Alberta (APEGGA).
Qualified Person
Someone who, by possession of a recognized degree, certificate or professional standing, and 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.
Qualified Welder
A person who is both certified and qualified as follows: CERTIFIED: Person who holds a certificate issued under the Alberta Apprenticeship and Industry Training Act or holds an Interprovincial Standards “Red Seal”. QUALIFIED: Person qualified by the Canadian Welding Bureau to CSA Standard W47.1.
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A p p e n d i x
B
Sample Fall Protection Plan SOURCE:
Occupational Health and Safety Code Explanation Guide Part 9 Figure 9.6 Sample fall protection plan
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S T RU C T U R A L S T E E L E R E C T I O N B E S T P R AC TICE S
STRUC TUR AL STEEL EREC TION BEST PRAC TICES
TO ORDER THIS BOOKLET, OR FOR MORE INFORMATION, CONTACT: an Alberta MHSA Office at www.mhsa.ab.ca or an ACSA office at www.acsa-safety.org
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