Specific guidelines are set in both Canada and the USA for the safe rigging of mass timber elements. These guidelines are included in the health and safety regulations of each specific jurisdiction where the project is taking place. A safety factor or design factor is established in these regulations that must be included in all components used for element rigging, including the rigging anchors. This blog post summarizes the minimum required safety factor for British Columbia, Ontario, and Quebec in Canada and OSHA requirements in the USA and shows how MTC Solutions rigging anchors are compliant with these regulations.
Approximately 6-minute read
In Canadian regulation, a “design factor” is defined as the theoretical reserve capability of a product, usually determined by dividing the breaking strength by the working load limit. These regulations also define rigging equipment as fiber ropes, wire ropes, chains, slings, attachments, connecting fittings, and associated components.
British Columbia (BC)
In BC, the Workers Compensation Act: Occupational Health and Safety Regulation sets the acceptable design factor required for rigging. Part 15.6 of this regulation requires a minimum design factor of 5 for all rigging components. This includes the anchor attachment system as per the definition. Other regulating bodies such as WorkSafe BC also includes additional specific requirements for rigging elements on-site.
In Ontario, the Occupational Health and Safety Act- Ontario Regulation 213/91: Construction Projects sets the acceptable design factor required for rigging. Section 172. (1) (d) of this regulation requires a minimum design factor of 5 for all rigging components. This includes the anchor attachment system as per the definition. Other regulator bodies such as IHSA also include a detailed manual for proper rigging practices on a construction site and guidelines for calculating working load limits
In Quebec, the Safety Code for the construction industry: Act Respecting Occupational Health and Safety regulation sets the acceptable design factor required for rigging. Chapter S-2.1, r.4 section 3.9.13 (4)(a) of this regulation requires hoisting to be in compliance with the Hoisting and Rigging Safety Manual of the Construction Safety Association of Ontario. Based on the IHSA manual, a minimum design factor of 5 for all rigging components is needed. This includes the anchor attachment system as per the definition. Other regulator bodies in Quebec, such as the CNESST, include additional specific requirements for site safety and should be followed.
United States Regulations
In the USA, the Occupational Safety and Health Administration (OSHA) sets regulations for proper rigging elements. Per Clause 1926.753(e)(2) of the OSHA Safety and Health Regulations for Construction section, all components used in rigging shall have at least a safety factor of 5. This includes every individual attachment point, including the rigging anchors.
MTC Solutions Rigging Systems
MTC Solutions Rigging Design Guide provides detailed information on various mass timber rigging anchoring systems. The anchor capacities in the guide are derived from the testing done on the system and directly include the required design factor of 5 set in Canadian and USA regulations.
The following is an example table from the USA Rigging Design Guide for flat CLT panel lifting using the Yoke 5T. A mean ultimate load of 27,810 lbs was recorded during the testing of the Yoke 5T with the Kombi ½”x 6-1/4” [12mmx 160mm] self-tapping screws. With the OSHA safety factor of 5 included in the reported capacities of the system, the design value becomes 5,500 lbs, as seen in the last row of the table.
For proper site safety, the Rigging Design Guide includes additional safety considerations such as modification factors when determining the element weight with various sling angles, safety factors for different rigging situations (in open or tight space), and dynamic acceleration the elements being lifted.
When rigging mass timber elements, all elements must always follow site safety requirements of the jurisdiction the project is located in. It is the responsibility of the rigging engineer and site supervisors to ensure proper rigging equipment is used with a minimum safety factor of 5. It also must be confirmed if anchoring devices directly include this safety factor in the reported design values or if the values must be adjusted. Proper rigging practices will ensure a safe working environment for workers and can reduce potential on-site injuries associated with these activities. Check our Rigging Design Guide for more information.