Section 26.3, subsection 8 states,
“The following additional requirements apply to a guardrail system that is made of wire rope:
1) The top rail and intermediate rail shall be made of wire rope that is at least 10 mm in diameter, and the rope shall be kept taut by a turnbuckle or other device.
2) The outward deflection of the top rail and the intermediate rail resulting from the loads specified in subsection (5) shall not exceed beyond the edge of a work surface.
3) The system shall have vertical separators at intervals of not more than 2.4 metres and horizontal supports at intervals or not more than 9 metres.
For those that have not read the post explaining the force load requirements that were explained in subsection 5, I will repeat the standards.
1. A point load of 675 newtons applied in a lateral direction for the top rail;
2. A point load of 450 newtons applied in a vertical downward direction to the top rail;
3. A point load of 450 newtons applied in a lateral or vertical downward direction to the intermediate rail, or midway between the top rail and the toe board;
4. A point load of 225 newtons applied in a lateral direction to the toe board
The force requirements do not change because of a different style or makeup of the posts and rails, which in this case, discusses wire rope instead of 2X4 posts or other type wooden device. Whatever the makeup, subsection 5 applies. All force requirements MUST be met and adhered to and do not change for any material.
It also makes sense that the wire rope reported in this subsection needs to be taut just to ensure that the force requirements are met. There is also more protection with a taut system than one without.
That goes without saying.
The 2.4 metres between vertical supports is exactly the same support as a wooden guardrail system. The horizontal supports, not to be more than 9 metre intervals, is a new piece of information. Again, the force requirements MUST be met, and I believe the regulation has had to be influenced but professional engineer(s), possibly someone with a structural engineer, one with a working knowledge of the ‘Building Code’.
Either way, the MOL will enforce the regulations to ensure that all employers understand the full extent of force loads for guardrail systems and the implications for those not adhering to the standards.
Remember — In Ontario, “ALL Accidents are Preventable”
‘Work’ and ‘Play’ safe.
Daniel L. Beal
CHSEP – Foundation Level
VP & Senior Trainer