An open and shut case: Carabiner design in Drops prevention

An open and shut case: Carabiner design in Drops prevention

On offshore oil and gas (O&G) rigs, working at height is commonplace. Carabiners have long been used both during rope access operations and to secure equipment at height – including safety securing solutions such as Drops prevention Nets.

‘Off the shelf’ carabiners, however, are not specifically designed for the unique technical and usability requirements of Drops prevention or use in harsh operational environments such as the offshore energy industry.

Dropsafe has always gone beyond accepted best practice to ensure the highest levels of safety and usability. This critical approach resulted in the design of the Trisafe™ Carabiner, a reimagined carabiner that provides extra security for the new Dropsafe Net. Using an innovative ‘triple action’ mechanism, the Trisafe™ prevents accidental opening, and therefore reduces the likelihood of human error.

We spoke to Mike Rice, Dropsafe’s Commercial Director, and Product Design Engineer Luke Richie, to explore how carabiners were typically used in Drops prevention and get a behind-the-scenes look at the development of the Trisafe™ Carabiner.


Carabiners in O&G

Carabiners are now deployed routinely in industries such as energy to tether safety securing nets to fixtures, but this was not always the case. Historically, personnel used U-bolts and shackles to attach safety securing solutions onto structures; a commonly used mechanism was the two-piece shackle. This created further challenges as it required a tool to open and close, increasing Drops risks when used at height.

At the time, the traditotional carabiner was an easy to procure component that ticked more boxes than other off the shelf products. The design of carabiners has not reflected the realities faced by technicians offshore, however.

Equally, the use of poorly manufactured, carabiners for offshore Drops prevention further risks compromising safety. The initial carabiners used by operators had no screw locks, just a single action open mechanism. Reverse snagging by wires and vibration can lead to these carabiners opening, reducing the effectiveness of the overall solution.

Although these are important factors, Dropsafe identified human error as a primary obstacle in improving the safety of carabiners in Drops prevention solutions. Mike Rice explains:

“Maintenance technicians are highly trained, competent professionals, but they are human, and like all humans, they are not infallible. They may on occasion fail to tighten carabiner screw locks fully. In offshore environments, cold weather and bulky protective gloves can compound the issue, reducing manual dexterity. When using solutions with fiddly, tight screws, locking and unlocking the carabiner multiple times can quickly become frustrating, increasing the chance of incorrect carabiner use.”


What was the R&D process for the Trisafe™ Carabiner?

Dropsafe had previously adapted the standard carabiner to incorporate an additional screw lock and spring, adding a further level of safety to its Net. Through continued industry engagement, however, it was clear that there were still further opportunities to reduce human error.

Mike recalls: “We listened carefully to the frustrations rig professionals had with carabiners in general. Before the pandemic we were very active on the O&G conference circuit, and in 2019, the discussion around carabiners for tool tethering was growing in prominence.

“It was important to capture industry feedback from engineers and rope access personnel across industries including power generation, mining and energy. We put the focus on launching the best product possible rather than delivering with an arbitrary timescale. The Trisafe™ is the cumulative result of almost 40 iterations, driven forward and refined by usability and testing results.”

The innovative integrated dual lever design of the Trisafe™ was made possible by advanced fabrication techniques, demonstrating the continual innovation in Drops prevention best practice unlocked by new materials and engineering knowledge.

Luke elaborates: “We were excited to use the latest Metal Injection Moulding processes. This means we can create an intricate shape and operating mechanism that couldn’t be achieved with traditional methods. Producing such a high tolerance specific shape would be very labour intensive with CNC, but, using high-quality 316 stainless steel, MIM keeps the strength high and the weight low.”


Engineering human error out of Drops prevention

The Trisafe™ Carabiner is designed to anticipate and tackle real-world challenges faced by industrial professionals to support better drops prevention. Critically, the Trisafe™ is ideally suited for safe use at height and is a key component of the new Dropsafe Net.

As such, its key features, driven by Dropsafe’s extensive R&D process, include:

  • Single hand operation to enable safer use, especially by rope-access technicians.
  • Tool-free installation to eliminate creating additional Drops risks.
  • Enabling Dropsafe Nets to now use one Trisafe instead of two carabiners, making installation more intuitive
  • An auto-locking spring and simple triple-opening mechanism to significantly reduce human error, even in cold, wet, and windy conditions.
  • An integrated design to prevent inadvertent disassembly or loosening.
  • Specifically designed to hook onto the new Dropsafe Choke Plate wire, ensuring easy installation and added security for the new Dropsafe Net.


Mike concludes: “As we supply Nets to customers around the world, we focused on combining this safety factor and human error reduction with ease of use and ease of installation. Our goal was to engineer human error out, striking a balance between the level of safety, and the level of usability. Fundamentally, the new Dropsafe Net is only as good as is weakest component, so ensuring that every part of the solution is industry-leading was key.”


To find out more about the new Dropsafe Net, and how the Trisafe™ carabiner adds an additional level of security, please visit the product page here.