Fall Protection
Fall Protection and Roof Trusses
A Fall Protection system may Include: • Guardrails • Travel restraint or fall arrest system • Safety net • Control zone, or • Some other equally effective means that protects the worker from falling.
Occupational Health and Safety Code Part 9
Part 9
Fall Protection
General protection 139(1) An employer must ensure that workers use a fall protection system at a temporary or permanent work area if (a) a worker may fall 3 metres or more, or (b) there is an unusual possibility of injury if a worker falls less than 3 metres.
Fall protection plan 143(1) An employer must develop procedures in a fall protection plan for a work site if a worker at the work site may fall 3 metres or more and workers are not protected by guardrails. (2) A fall protection plan must specify (a) the fall hazards at the work site, (b) the fall protection system to be used at the work site, (c) the procedures used to assemble, maintain, inspect, use and disassemble the fall protection system, and (d) the rescue procedures to be used if a worker falls, is suspended by a personal fall arrest system or safety net and needs to be rescued.
This fall protection plan must in writing and available at the work site.
Personal Fall Arrest System
Personal Fall Arrest System A fall arrest system arrests a worker’s fall to prevent injuries; it does not prevent a worker from falling. An Engineered system must be used.
Travel Restraint System A travel restraint system prevents a worker from traveling to an edge or position from which the worker could fall.
Travel Restraint System
Anchors for personal fall arrest systems or a travel restraint system attached to trusses must not be used until the trusses are completely installed including all bracing and sheathing.
Fall Protection and Roof Trusses
A falling worker attached to a single truss can cause all the trusses on the structure to collapse in a domino effect
Roofers get an exception (Part 38) for 3 years. Roofers may use slide guards if: The fall height is less that 6 metres and the slope of the roof is 6/12 or less.
Fall arrest anchors 154(1) An employer must ensure that anchor points to which a personal fall arrest system is attached have an ultimate load capacity of at least 22.2 kilonewtons per worker attached, in any direction in which the load may be applied. (2) Subsection (1) does not apply to anchor points installed before April 30, 2004. (3) Subsection (1) does not apply to the anchor points of horizontal lifeline systems that must meet the requirements of section 157(1)(e).
(4) If the structure to which the anchor point is attached is not capable of withstanding a 22.2 kilonewtons force without damage, the employer may use an anchor point designed, installed and used as part of a fall protection system that is capable of withstanding twice the maximum arresting force that the anchor point is subjected to. (5) The employer must ensure that the anchor point described in subsection (4) is designed, installed and used or
(a) in accordance with the manufacturer’s specifications, (b) specifications certified by a professional engineer. (6) An employer must ensure that anchor points to which a personal fall arrest system is attached are not part of an anchor used to support or suspend a platform.
A fall arrest anchor point must be strong enough to support the weight of a pick-up truck.
Travel restraint anchors — temporary 152(1) An employer must ensure that a temporary anchor point used in a travel restraint system (a) has an ultimate load capacity of at least 3.5 kilonewtons in any direction in which the load may be applied, and (b) is installed, used and removed according to the manufacturer’s specifications. (2) The employer must ensure that the temporary travel restraint anchor point described in subsection (1) is (a) permanently marked as being for travel restraint only, and
(b) removed from use on the earliest of (i) the date the work project for which it is intended is completed, or (ii) the time specified by the manufacturer.
Travel restraint anchors — permanent 153(1) An employer must ensure that a permanent anchor point used in a travel restraint system associated with a construction project involving typical methods of constructing wood-framed, sloped-roof structures (a) has an ultimate load capacity of at least 8.75 kilonewtons in any direction in which the load may be applied, (b) is installed and used according to the manufacturer’s specifications, and (c) is permanently marked as being for travel restraint only.
Section 153 Travel restraint anchors – permanent For typical wood-frame, sloped-roof construction During preparation of the OHS Code, field tests conducted under the supervision of a structural engineer confirmed that a typical truss construction roof built according to the Alberta Building Code begins to fail when pulled with a load of 8.75 kilonewtons (2000 pounds-force). While a roof’s structure can be strengthened to withstand a greater load, many roofs would require multiple anchors, up to 6 in some cases. It would be impractical to strengthen the roof to this degree to support permanent travel restraint anchors without significant cost implications.
Table 9.1 Summary of travel restraint system load capacities Load carrying capacity 3.5 kilonewtons (800 pounds-force)
Circumstances Temporary anchor for travel restraint systems
8.75 kilonewtons (2000 pounds-force)
Permanent anchor for travel restraint systems -limited to construction projects involving typical residential-style construction methods
22.2 kilonewtons (5000 pounds-force)
Permanent anchor for travel restraint systems – to be used in all applications except construction projects involving typical residential-style construction methods
What does the Truss Industry have to do?
Each Industry in the team has responsibilities & duties.
BUILDER/BUILDING DESIGNER
The builder/building designer is responsible for the overall building and that it is designed in accordance with the Alberta Building Code in effect. This responsibility includes, but is not limited to, the design of foundations, columns, headers, beams, bearing conditions and load transfer.
The Builder/Building Designer shall prepare and provide Construction Design Documents that specify:
•The location, direction and magnitude of all dead, live and construction loads applicable to each floor and roof section including, but not limited to, loads attributable to: roof, floor, partition, mechanical, fall protection anchorage, fire sprinkler, attic, storage, wind, snow drift and seismic;
•The building classification and any requirements over and above code requirements;
•The Handling, Bracing and Installation Guidelines to be used when installing the “I” joists, engineered beams and trusses;
•Any Permanent Bracing required for the structure including the bracing required to anchor or restrain the lateral truss bracing;
•The locations and type of Travel Restraint Anchors or Fall Arrest Anchors that will be used if a Fall Protection Plan is required.
•The method and procedure to be used when installing travel restraint or fall arrest anchors.
Anchor Spacing
Anchor
Roof Ridge
Life Line
Maximum distance a worker can lean over to reach work
Roof Eave
TRUSS MANUFACTURER The Truss Manufacturer is responsible for using the most recent version of all Engineer-Approved Computer Design Programs (trusses, “I” joists and beams) and for ensuring that all users be competent and trained by the software supplier(s). An engineer registered in the province of Alberta must approve all software. All metal truss connector plates, “I” joists, engineered beams and hangers must be listed by the Canadian Construction Material Centre (CCMC). The Truss Manufacturer shall ensure that: •A Truss Design Drawing is prepared for every truss manufactured and identified by markings • corresponding with those on the layout drawing; •Each truss is loaded and designed to meet the specifications of the Construction Design Documents; •All trusses are manufactured in accordance with the final approved Truss Design Drawings using • the Western Wood Truss Association of Alberta (WWTA-AB) quality criteria or equivalent; •A truss layout drawing is provided that includes truss designations, their placement, bearing • conditions and special hardware including fall protection anchor attachment locations; •Where possible, the web configuration is consistent to facilitate the lateral bracing requirements; •Hangers as specified on the truss layout drawing and supplied for truss-to-truss connections • can be installed as per the hanger manufacturer’s instructions; •All special nails/fasteners are provided when required by the hanger manufacturer’s specification; •A package of documents and instructional information be delivered with every shipment of trusses that includes: Truss design drawings for all trusses included in shipment; Truss placement drawing; Handling, Bracing and Installation Guidelines (WWTA-AB pamphlet or equivalent); Instructions on how to properly install the structural cross bracing (“bracing of the bracing”); Hanger manufacturer’s instructions and nail specifications; Special instructions as needed (Girder lamination, “T” braces, etc.); List of trusses and materials shipped.
•Every truss is clearly identified by markings on the bottom of the bottom chord corresponding with those on the truss layout drawing; •Every truss is clearly marked to show the name of the manufacturer; •Bottom chord bearing parallel chord trusses are clearly marked to prevent inverted installation; •Trusses having bearing locations other than at the end or heel locations or are not symmetrical have bearing locations clearly marked; •Trusses carrying point loads, other than symmetrical, have the point load locations clearly marked; •Trusses designed for the attachment of specified fall protection anchors are clearly marked.
Temporary Travel Restraint Anchors
800 lbs
Permanent Travel Restraint Anchors
2000 lbs
Fall Arrest Anchors
5000 lbs
Fall Arrest Anchors
5000 lbs
Would require 50 - 3 ½” nails
FRAMER/CONTRACTOR
The Framer/Contractor is responsible for the field storage, handling and safe installation of trusses, “I” joists and engineered beams including, but not limited to, temporary bracing, permanent bracing, anchorage and field assembly of all components in accordance to the Construction Design Documents, Truss Design Drawings, Truss Layout Drawing and Floor Layout Drawing.
The Framer/Contractor shall ensure that:
•Workers handling and installing engineered wood products be trained in the installation of these products; (Members of the WWTA-AB recommend that only workers who have attended WWTA-AB training sessions for the “Installation of Engineered Wood Products” or have completed the “Residential Truss Systems” module offered by Alberta Learning through the carpentry programs at the various colleges and technical institutes around Alberta be allowed to install Engineered Wood Products);
•Proper equipment and safety procedures are used when erecting and installing engineered wood products;
•The strongbacks used for lifting trusses or pre-assembled roof sections have adequate strength and stiffness to safely carry the weight. Care must be taken to avoid damaging or overstressing any truss member or joint.
•The trusses are placed according to the truss layout drawing and that all web lateral braces are located and attached according to the truss design drawing;
•All instructions for connecting multiple trusses, attaching hangers and fall protection anchors are followed and located as shown on the truss layout drawing;
•All “T” braces be installed in accordance with truss design drawings;
•All hip girder and hip trusses are blocked as shown on the truss layout drawing; (these blocks are required to restrain top chords from buckling);
•All permanent bracing is installed as per the Construction Design Documents;
•Any damage to trusses is immediately reported to the truss manufacturer and that the required repairs are made
Types of Temporary Travel Restraint Anchors
NORTH Spectra Loop Sling
Types of Temporary Travel Restraint Anchors
Types of Temporary Travel Restraint Anchors
80 0 lb s
Types of Temporary Travel Restraint Anchors
Types of Temporary Travel Restraint Anchors
Types of Permanent Travel Restraint Anchors
20 00 lbs
Shepherd Permanent Roof Anchor
Types of Permanent Travel Restraint Anchors
Types of Permanent Travel Restraint Anchors
Rose Permanent Roof Anchor
Installing Trusses and Being Compliant with the New Health & Safety Code