Anchor points for fall protection

An anchor is the secure point that a fall protection system is attached to, and every other part of the system depends on it. A suitable anchor is strong enough for the forces involved, located so the worker is protected without dangerous swing or inadequate clearance, compatible with the equipment, and either engineered or meeting the strength your province requires. Pipes, railings and conduit are not anchors just because they are nearby.

What makes an anchor suitable

Strength

Each province sets minimum strength requirements for anchors, which differ for fall arrest, travel restraint and other systems. A fall arrest anchor must withstand much higher forces than a restraint anchor. Anchors that do not meet the prescribed strength must instead be designed by a professional engineer for the system and loads involved. The CSA Z259 series, including standards for anchorage connectors and for the design of active fall protection systems, is the main Canadian reference. Check the current editions and your province's rules.

Location

• Overhead where possible. An anchor above the worker reduces free fall distance and the force on the body.
• Clearance. There must be enough distance below the worker for the free fall, the deployment of any energy absorber, harness stretch and a safety margin, so the worker does not strike the ground or a lower level.
• Swing fall. An anchor off to the side causes the worker to swing like a pendulum after a fall and strike nearby objects. Keep the anchor as directly overhead as practical.
• Edges. Lines passing over sharp edges can be cut. Use equipment rated for leading edge use where this cannot be avoided.

Compatibility

The connector must fit the anchor properly without side-loading the gate or forming an unsafe connection. Anchorage connectors, such as beam clamps, cross-arm straps and roof anchors, should be used only as the manufacturer directs.

Types of anchors

Permanent roof anchors on buildings

Many commercial buildings have roof anchors for window cleaning, rooftop equipment maintenance and roof repairs. For building owners and property managers, these anchors are a responsibility that is easy to overlook. A sound approach includes:

• Engineered drawings showing anchor locations, capacity and intended use
• A roof anchor plan posted at roof access points so workers know which anchors to use and how
• Labels on each anchor identifying its use and capacity
• Periodic inspection and, where required, testing by qualified people, at the interval your province and the designer specify
• Inspection after any roof work that could have affected the anchors or their attachment
• Records of installation, inspection, testing and repairs
• A requirement that contractors use the designated anchors and follow the plan

Roof re-covering, new rooftop equipment and water damage can all compromise anchors and their attachment to the structure. If anchors have no documentation or have not been inspected in years, treat them as unverified until they have been assessed.

Questions to ask about an existing roof anchor

• Is there a drawing or certification letter that identifies this anchor, its capacity and its intended use?
• Is it labelled, and does the label match the documentation?
• When was it last inspected or tested, and by whom?
• Has the roof been re-covered, or equipment added, since it was installed?
• Is there visible corrosion, movement, damaged flashing or ponding water around the base?
• Does its location create swing fall or clearance problems for the tasks done near it?
• Is there a way to rescue a worker suspended from it?

If the answer to the first question is no, the anchor should be treated as unverified. That does not necessarily mean it is unsafe, but nobody can show that it is suitable until an engineer has reviewed it.

A typical case

A property manager takes over an older office building. The roof has several anchors, but there are no drawings and nobody knows when they were last inspected. The roof was re-covered a few years ago. Window cleaning and rooftop unit maintenance are scheduled within weeks. A sensible sequence is to suspend use of the anchors, arrange temporary measures for the urgent work that do not depend on them, such as working back from the edge with a guardrail or using a properly installed temporary anchor system, and engage an engineer to assess the existing anchors, their attachment and their documentation. The outcome is either a certified anchor plan for the roof, or a list of anchors to replace or remove, and in both cases a posted plan at the roof hatch so contractors know which anchors they may use.

Horizontal lifelines

Horizontal lifelines let one or more workers move along a length of roof, beam or platform while staying connected. They create large forces at their end anchors and sag significantly when a fall is arrested, which increases clearance needs. Temporary horizontal lifelines should be used only as the manufacturer directs, and custom or permanent systems must be designed by a professional engineer.

Planning anchors into the work

Anchor selection belongs in the fall protection plan, before workers are on the roof. The plan should name the anchors, show how the system will be connected and give the clearance calculation. It also needs to describe how a worker suspended from that anchor will be rescued, which may need its own anchor point. See The fall protection hierarchy and Fall rescue plans. Roof condition affects anchors too, and our roof inspections look at the roof as a whole.

How ehZee can help

We review existing anchors and their documentation, identify gaps, and coordinate engineering and testing where anchors need to be designed or certified. See our lift safety and fall arrest service.

Common questions