An unprotected opening on a work surface is a serious hazard that puts employees at risk of injuries from falls. Guardrails are the preferred method for protecting workers near openings but may not always be practical. In such cases, securely fastened protective covers — planks, plywood, or steel plates — may be the best alternative.
Protective coverings may be removed temporarily to perform work in or around the opening. Workers must be adequately protected and signs posted. Every warning sign must have the word "DANGER" clearly written and be at least 150 millimetres in height. Warning signs must also indicate that unauthorized people are not allowed around uncovered openings.
O. Reg. 213/91
Part II GENERAL CONSTRUCTION
26.3 (1) Despite paragraph 1 of section 26, a guardrail system that meets the requirements of this section shall be used if a worker has access to the perimeter or an open side of any of the following work surfaces and may be exposed to a fall of 2.4 metres or more:
1. A floor, including the floor of a mezzanine or balcony.
2. The surface of a bridge.
3. A roof while formwork is in place.
4. A scaffold platform or other work platform, runway or ramp.
(2) One of the following precautions shall be used to prevent a worker from falling through an opening on a work surface:
1. A guardrail system that meets the requirements of this section.
2. A protective covering that,
i. completely covers the opening,
ii. is securely fastened,
iii. is adequately identified as covering an opening,
iv. is made from material adequate to support all loads to which the covering may be subjected, and
v. is capable of supporting a live load of at least 2.4 kilonewtons per square metre without exceeding the allowable unit stresses for the material used.
(3) The guardrail system or protective covering required under subsection (1) or (2) may be removed temporarily to perform work in or around the opening if a worker is adequately protected and signs are posted in accordance with subsections 44(1) and (2).
(4) The following are the specifications for a guardrail system:
1. It shall have a top rail, an intermediate rail and a toe board.
2. The intermediate rail may be replaced by material that can withstand a point load of 450 newtons applied in a lateral or vertical downward direction.
3. Subject to subsection 116 (8), the top of the guardrail system shall be located at least 0.9 metres but not more than 1.1 metres above the surface on which the system is installed.
4. The intermediate rail shall be located midway between the top rail and the toe board.
4.1 The toe board shall extend from the surface to which the guardrail system is attached to a height of at least 89 millimetres.
5. If the guardrail system is located at the perimeter of a work surface, the distance between the edge of the surface and the guardrail system shall not be greater than 300 millimetres.
(5) A guardrail system shall be capable of resisting anywhere along the length of the system the following loads when applied separately, without exceeding the allowable unit stress for each material used:
1. A point load of 675 newtons applied in a lateral direction to 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.
(6) The distance between any two adjacent posts of the guardrail system may be greater than 2.4 metres only if the system is capable of resisting the loads specified in subsection (5) increased in proportion to the greater distance between the posts.
(7) The following additional requirements apply to a guardrail system that is made of wood:
1. The wood shall be spruce, pine or fir (S-P-F) timber of construction grade quality or better and shall not have any visible defect affecting its load-carrying capacity.
2. The wood shall be free of sharp objects such as splinters and protruding nails.
3. The system shall have posts that are at least 38 millimetres by 89 millimetres, are securely fastened to the surface and are spaced at intervals of not more than 2.4 metres.
4. The top rail and the intermediate rail shall each be at least 38 millimetres by 89 millimetres.
(7.1) If a guardrail system that is made of wood is constructed and installed so that it is capable of resisting all loads that it may be subjected to by a worker, the following do not apply:
1. The requirement in paragraph 2 of subsection (4) that the replacement material can withstand a point load of 450 newtons.
2. Subsections (5) and (6).
(8) 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 millimetres in diameter, and the rope shall be kept taut by a turnbuckle or other device.
2. The outward deflection of the top rail and intermediate rail resulting from the loads specified in subsection (5) shall not extend 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 of not more than 9 metres.
4. Repealed. [O. Reg. 443/09, s. 2]
[O. Reg. 145/00, s. 14; 443/09, s. 2; 345/15, s. 6]
44. (1) Signs meeting the requirements of subsection (2) shall be posted in prominent locations and in sufficient numbers to warn workers of a hazard on a project.
(2) A sign shall contain the word "DANGER" written in legible letters that are at least 150 millimetres in height and shall state that entry by any unauthorized person to the area where the hazard exists is forbidden.
(3) Without limiting the generality of subsection (1), a sign shall be posted,
(a) adjacent to a hoisting area;
(b) under a boatswain's chair, or a suspended work platform;
(c) at the outlet from a chute;
(d) at a means of access to a place where there may be a noxious gas, vapour, dust or fume, noxious substance or a lack of oxygen; and
(e) where there is a potential hazard from an energized overhead electrical conductor at more than 750 volts.
(4) No person shall enter an area in which a sign is posted other than a worker authorized to work in the area.
[O. Reg. 242/16, s. 6; 142/17, s. 9]