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    Fall protection connectors, the critical link.

    December 14, 2020
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    Fall protection connectors, the critical link.

    • A fall protection system is an assembly of interconnected items comprising of a full-body fall protection harness attached to an anchorage point, typically by means of a shock absorbing lanyard. This approach makes use of the ABC’s of fall protection to stop a falling person under safe conditions and is designed to prevent the worker from hitting the ground, next level or any other obstructions below. However, the self-retracting lifeline (SRL) is becoming more common on job sites. Making them an increasingly popular choice over shock absorbing lanyards, especially since they have become smaller, lighter and more economical, and because they have the added advantage to reduce fall distance and fall clearance requirements.

    • The difference between a shock absorbing lanyard and a self-retracting lifeline?

    • Shock absorbing lanyards include a shock absorber and can be constructed from rope, webbing, or cable, in a variety of lengths and configurations to meet the needs of a variety of applications. Lanyards should be long enough to ensure usability, while remaining as short as possible to minimise free fall distance, with a maximum length of two metres. In the event of a fall, the shock absorbing lanyard is designed to tear internally, slowing the rate of the fall and reducing the fall arrest forces.

      A self-retracting lifeline is a fall arrest device incorporating a lifeline that extends and retracts as a worker moves away from and towards the unit. In the event of a fall, an energy-absorbing, quick-activating brake system stops the fall while reducing fall arrest forces and fall distances to safe levels, within one metre. The lifeline is made of either galvanised or stainless steel cable or webbing. SRL’s are typically used when a great deal of mobility is needed on a job site. The amount of mobility is limited only by the length of the SRL’s lifeline, which can range from 1.8 to 60 metres, or greater. However compact SRL’s that connect directly to the harness as a lanyard replacement are generally 1.8 metres in length, utilise a shock absorber (personal energy absorber) and are commonly referred to as Personal SRL’s.

      Whether using a shock absorbing lanyard or a self-retracting lifeline, as per AS/NZS 1891.1, AS/NZS 1891.4 & AS/NZS 1891.5 requirements, the fall arrest system must:

      • Keep the forces on the human body below 6 kN (600 kg) when using a full-body harness - the force imposed upon the worker the moment the fall arrest system stops the fall.
      • Limit the free fall distance to less than 2 metres - free fall is the distance travelled from the point where the worker starts falling to the point where the workers’ fall arrest system begins to slow the worker down.

      The shock absorbing lanyard or personal SRL both work to limit the fall arrest forces and minimise the free fall distances to the required levels, however another important factor to consider is fall clearance. Determining fall clearance, the distance from the work area to the ground or obstructions below is a critical safety factor that requires careful consideration in any fall protection system.

    • Fall clearance considerations, lanyards versus SRL’s.

      When using a fall arrest system, it is essential to determine if the available fall clearance, the minimum vertical distance a worker needs in the event of a fall, is sufficient to safely arrest the fall and avoid striking the ground or an object below. It’s crucial to understand that fall clearance is more than just the simple measurement from a worker to the nearest obstruction. Other factors to consider include deceleration distance, the height of the worker and whether a shock absorbing lanyard or self-retracting lifeline is being used. In fact, a correct calculation could mean the difference between serious injury and a safely arrested fall. If the distance between the anchorage point and the nearest obstruction is less than the calculated fall clearance distance, the fall arrest system cannot effectively protect a worker from the dangers of a fall from height. Diagrams and formulas for calculating fall clearances are outlined below.

    Shock absorbing lanyard.
    Self-retracting lifeline.
    • The evolution of the self-retracting lifeline.

      In the past, workers at heights relied on energy-absorbing lanyards attached to anchor points to help protect themselves from falling. As equipment evolved, self-retracting lifelines were added to the fall protection package to meet the needs of construction and industrial work methods and challenges. SRL’s have distinct advantages over lanyards but are more expensive. With time, they have become shorter and lighter for personal use. Compared to their predecessors, these newer personal SRL’s are designed to attach directly to a user’s harness. Which raises the question, why would you need a lanyard if these SRL’s can be attached to a harness? The answer is that you don’t. These shorter personal SRL’s, are lightweight, compact, and most importantly, arrest a fall just like their larger counterparts. Although you may pay slightly more for personal SRL’s in comparison to lanyards, they have some distinct advantages over the traditional shock absorbing lanyard.

      The advantages of personal SRL’s over lanyards:

      1. They require shorter fall clearance distances.
      2. They don’t allow slack in the line, thereby minimising free fall distances and allowing them to arrest falls quicker.
      3. Lanyards are a fixed-length product, even though adjustable lanyards are available, once adjusted to the required length they are fixed and need to be continually readjusted as your work position changes, while SRL’s retract and deploy based on the user’s position. This keeps the lifeline off the ground and out of the way, making work easier and helps reduce tripping hazards.
      4. Because the lifeline pays in and out of the housing, it does not get dragged along the ground, so it stays cleaner and gets less wear.
      5. SRL’s do not wear out as quickly as lanyards – they will normally outlast a lanyard significantly. This means that their higher cost is often offset by their longevity.
      6. They are ideal for foot-level tie-off applications - they enable users to tie off at their feet in many situations where there is no anchor available above the user’s head.*
    • 3M™ DBI-SALA® Nano-Lok™ 2G Personal Self-Retracting Lifeline.

      The new 3M™ DBI-SALA® Nano-Lok™ 2G Personal Self-Retracting Lifeline is trusted for its reliability and durability, the Nano-Lok™ has long been the workhorse personal SRL of the industry. Our latest version, the second generation, doesn’t just match the performance of the outgoing model - it surpasses it and then some. It’s sleeker with a more compact design. It’s tougher with a longer lasting cover. It’s easier and faster to connect.

      Nano-Lok™ is ergonomically designed for ease-of-use and is ideal for direct connection to most harnesses. The extremely compact and lightweight design is virtually unnoticeable on your back, staying out of the worker’s way and making it ideal as a lanyard replacement. Whether your application requires single or twin leg configurations, mounting to an overhead anchor, foot-level tie-off, or for connection directly to a harness, there are a variety of models to choose from to suit almost any application. Nano-Lok™ locks quickly - stopping a fall within centimetres, providing more protection at low heights. In addition, tension is always kept on the lifeline, which reduces dragging, snapping and trip falls.

    • 3M™ DBI-SALA® Nano-Lok™ 2G Personal SRL

      Light on weight, heavy on features:

      • Fast connection system - simple, light-weight connector allows backward compatibility.
      • Optional twin pin connector - easily add or remove Nano-Lok legs without removing the connector from the harness.
      • Sleek, durable nitrile rubber energy absorber - new look design that minimises overall size.
      • Single-leg anchorage connector - attaches directly to the back of most harnesses Installs to the webbing, leaving the dorsal D-ring free for other equipment or rescue.
      • 1.8 m 19 mm dynema polyester web lifeline - the synthetic lifeline reduces overall weight and the retractable design provides freedom of movement, keeps the lifeline out of the worker’s way reducing dragging, snagging and trip falls.
      • Self-locking connectors on lifeline - models available with either snap hooks, scaffold hooks or triple action karabiners that automatically lock and close for added safety.
      • Extremely compact, lightweight design - the device is virtually unnoticeable on your back, stays out of the way and can be easily used as a lanyard replacement.
      • Tough and impact resistant thermoplastic housing - compact and durable housing designed to withstand the demands of challenging job sites and built to last.
      • Swivelling anchorage loop - limits lifeline twisting for smoother operation and added worker satisfaction.
      • Quick activating speed sensing brake system - stops a falling worker within centimetres, providing more protection at low heights. Designed for smooth consistent operation, allowing the user to maintain a normal work pace without the interruption of constant lock ups.
      • High capacity external energy absorber and impact indicator - specialised built-in external absorption system maintains safe fall arrest forces for users and tools up to 140 kg and provides a visual alert that the SRL has been involved in a fall.
      • Connected safety equipped - built-in RFID identification tag helps the user record and store information on inspections.
      • Wide variety of configurations available - an extensive range of models to choose from to suit almost any application.

      Every at-height worker deserves to be safe and return home safely at the end of each day, no matter the size or nature of the job. The 3M™ DBI-SALA® Nano-Lok™ 2G range offers:

      • The highest safety standards - fully compliant to AS/NZS 1891.3:2020
      • Unmatched comfort - fast attachment of Nano-Lok™ single or twin leg SRL
      • Unparalleled performance - foot-level tie-off with 140 kg capacity.*

      For more information about the 3M™ DBI-SALA® Nano-Lok™ 2G Personal Self-Retracting Lifeline contact your 3M Fall Protection Specialist

      This article is a general guide, reach out to a 3M Fall Protection Specialist if you’re unsure of any aspect of fall protection or fall protection equipment.

      * The maximum distance below the user’s dorsal attachment in foot-level applications when the capacity is limited to 140 kg is 1500 mm.