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
| Type | Examples | Key points |
|---|---|---|
| Permanent engineered anchors | Roof anchors, davit bases, fixed horizontal lifelines, rigid rail systems | Designed and certified for the building, documented, labelled and inspected periodically |
| Temporary anchors | Beam clamps, cross-arm straps, roof anchors on construction sites, portable davits | Installed and used as the manufacturer directs, inspected before each use, removed when the work ends |
| Structural members used as anchors | Structural steel beams and columns | Must be assessed as capable of the required load by a competent person or engineer, with suitable connectors |
Not everything solid is an anchor. Ductwork, piping, conduit, cable trays, guardrails, ladders, roof vents and parts of mechanical equipment are not designed to take fall arrest forces. Never use them as anchors unless an engineer has specifically assessed them for that purpose.
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.
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
Can one anchor be used by more than one worker?
Only if it is designed and rated for multiple users. Most single-point anchors are for one worker at a time.
Who can certify a roof anchor?
Permanent anchors are normally designed and certified by a professional engineer, and installation and testing should follow the designer's and manufacturer's requirements. Rules vary by province.