Ladder Safety in Ontario: What the Regulation Actually Requires

The requirements below come from Ontario Regulation 213/91 (Construction Projects) sections 78 through 80 under the Occupational Health and Safety Act (OHSA), and CSA Z11-12 (Portable Ladders). These are the rules that govern every ladder on an Ontario construction site, and the rules a Ministry of Labour inspector will check when they see a worker on a ladder.

Why ladder falls keep happening

Ladders are the most common elevated work platform on construction sites, and they are involved in more workplace injuries than scaffolds, lifts, and platforms combined. The Ministry of Labour's enforcement data consistently shows ladder-related violations in the top five most common construction orders. The injuries are predictable: a worker sets up a ladder at the wrong angle and it slides out at the base; a worker reaches too far to the side and the ladder tips; a worker carries materials in both hands and loses their grip. Each of these failures maps directly to a specific rule in O. Reg. 213/91 or CSA Z11-12 — the 4:1 angle rule, the 0.3 m reach limit, and the three-point contact requirement. The regulation exists because decades of WSIB claims data proved that ladder injuries are almost entirely preventable with proper setup and use.

The 4:1 rule and the 3-foot extension (s.78)

Every extension ladder must be set up at a 75.5-degree angle. The practical way to achieve this is the 4:1 rule: for every 4 feet of working height, the base of the ladder should be 1 foot out from the support surface. A ladder leaning against a wall at 16 feet should have its base 4 feet from the wall. Too steep and the ladder can tip backward when the worker leans back; too shallow and the base can slide out under the worker's weight. This angle is not a suggestion — it is the engineered balance point where the ladder is most stable under load. Section 78 of O. Reg. 213/91 also requires that when an extension ladder is used for access to an upper level, it must extend at least 0.9 metres (3 feet) above the landing surface. This provides the worker with a handhold as they step from the ladder to the roof or platform. Without that extension, the worker's last handhold is at waist level as they step onto the landing — and that transition point is where a significant percentage of ladder falls occur.

Three-point contact and why it is not optional (s.78(2))

Section 78(2) requires workers to maintain three-point contact — two hands and one foot, or two feet and one hand — at all times while climbing. This rule exists because a human being climbing a vertical surface with only two points of contact is one slip away from a fall. Three points distribute the load across the ladder, keep the worker's centre of gravity between the side rails, and ensure that if one hand or foot slips, two other contact points remain. Carrying tools, materials, or equipment in your hands while climbing breaks three-point contact and is a violation. Use a tool belt, hoist line, or rope and bucket to move materials. The few seconds saved by carrying a drill up a ladder in one hand is not worth the risk — or the Ministry of Labour order that follows if an inspector sees it.

Securing the ladder (s.78(1))

Section 78(1) requires that portable ladders be secured to prevent them from slipping. This means tied off at the top, secured at the base, or held by a worker at the base. On a construction site, the most reliable method is tying the ladder at the top to a structural member — a roof truss, a wall stud, or a permanent anchor. If the top cannot be secured, the base must be held by another worker or secured with stakes, a ladder stabilizer, or non-slip feet on a firm surface. A ladder that is not secured relies entirely on friction between its feet and the ground surface, and friction fails without warning — wet grass, sawdust on concrete, gravel, ice. The resulting slide-out is fast and gives the worker no time to react. Unsecured ladders are one of the most common orders written by MOL inspectors on construction projects.

Electrical hazards and non-conductive ladders (s.78)

Section 78 prohibits the use of metal ladders near electrical hazards. An aluminum extension ladder that contacts a live overhead power line will kill the worker instantly — aluminum is an excellent conductor, and the current flows through the ladder, through the worker, and to ground before the worker can react. Even indirect contact — the ladder touching a wire while the worker is on the ground holding the base — can be fatal. Near any electrical hazard, only non-conductive ladders may be used. In practice, this means fiberglass. Wooden ladders were historically used near electrical, but wet wood conducts electricity, and job-made wooden ladders on a construction site are often wet. Fiberglass ladders rated for electrical work are clearly labelled with their dielectric rating. On any site where overhead power lines, transformers, electrical panels, or live conductors are present, fiberglass is the only acceptable material.

Duty ratings and why the label matters (CSA Z11-12)

CSA Z11-12 assigns duty ratings to portable ladders based on the maximum load they are designed to support. The rating includes the weight of the worker plus all tools, materials, and equipment carried on the ladder. Grade 3 supports 200 pounds (91 kg) and is intended for light household use — it has no place on a construction site. Grade 2 supports 225 pounds (102 kg) for commercial use. Grade 1 supports 250 pounds (113 kg) for heavy industrial use. Grade 1A supports 300 pounds (136 kg) for extra heavy-duty use. A 200-pound worker wearing a tool belt, carrying a drill, with a few pounds of fasteners, easily exceeds Grade 3 and pushes into Grade 2 territory. Add a bundle of shingles or a sheet of plywood and you need Grade 1 or 1A. The label on the ladder is not decoration — it is the manufacturer's engineering limit. Exceeding the duty rating risks structural failure of a rung, rail, or connection. On a construction site, Grade 2 is the practical minimum, and Grade 1 is the standard recommendation.

Pre-use inspection: what to check every time

Every ladder must be inspected before each use by a competent worker — someone with the knowledge and experience to recognize defects. The inspection takes less than a minute and checks: side rails for bends, cracks, dents, or corrosion; rungs for damage, looseness, or absence; feet and shoes for wear or absence; spreaders and locks for proper function (step ladders); rung locks for engagement (extension ladders); rope and pulley condition (extension ladders); labels for readability, including the duty rating; and all hardware for tightness. A ladder that fails any check must be immediately tagged and removed from service — not set aside for later repair, not "used carefully." A defective ladder that remains accessible on a site will be used by someone who did not see the defect, and the resulting injury is the employer's liability. Tagging defective equipment out of service is not optional under OHSA — it is a core employer duty under section 25(2)(h).

When a ladder is not enough

Ladders are designed for short-duration access and light tasks. When the working height exceeds 6 metres (20 feet), when the task requires both hands for an extended period, when heavy materials need to be moved to height, or when the work area requires lateral movement, a ladder is the wrong tool. Scaffolds, elevating work platforms (scissor lifts, boom lifts), and platform ladders provide a stable work surface, guardrail protection, and the ability to work with both hands. The cost of renting a scaffold or lift for a day is a fraction of the cost of a single fall injury — in medical costs, WSIB premiums, lost time, and regulatory penalties. The regulation does not prohibit ladder use at any specific height, but industry best practice and the Ministry of Labour's enforcement approach both recognize that relying on a portable ladder above 6 metres increases risk to the point where alternative equipment should be considered.