Falls from heights alone account for approximately 12% of all the workplace accidents that occur in the main sectors of the economy, found a previous study published by the IRSST in 2007. They are the primary cause of construction worker deaths.

Construction workers who install roof trusses are at risk of falling because they have to work at height in difficult conditions. Poised precariously on the framework, they may lose their balance or fall when putting trusses into place. To protect its workers from falling while installing trusses, plywood or shingles, a residential contractor recently developed a horizontal lifeline system (HLLS) consisting of two aluminum posts and a steel cable using the roof they are erecting as the host structure.

Although operational, this system is heavy and not very user-friendly, which is keeping it from being used on construction sites. Preliminary testing on a roof on which work had been completed showed that it has potential as a component of a fall-arrest system.

At the request of the sector-based OHS association ASP-Construction, the IRSST conducted a study with the aim of evaluating the HLLS to make it more efficient, user-friendly and reliable by improving the installation method and making it lighter. The researchers also aimed to confirm the strength of braced roof trusses as a host structure for a worker’s lanyard, the HLLS and anchoring connectors certified to standard CAN/CSA Z259.15 – Anchorage Connectors.

The HLLS passed all the drop tests and therefore met the performance and strength requirements for such a system. Furthermore, the contractor’s HLLS was improved by reducing the number of parts to make it easier to secure it to the host structure. This also reduced the system’s weight by at least 30%.

This HLLS gives workers greater mobility and protects them the entire time they are working, while also enhancing productivity. It therefore provides good protection against falls from heights for residential roofers. The cable turnbuckle from the original version of the contractor’s HLLS was removed in the study version to cut costs and facilitate testing, as it had no structural function. This improved version of the cable system, checked and validated by tests that meet the requirements of standard CSA Z259 respecting fall protection, will make it easier to use on construction sites.