HEIGHT SAFETY: YOUR LIFE HANGS IN THE BALANCE

In the big picture, the human body can be a frail structure. Compared, say, to a domestic cat, our ability to fall from height unscathed is pretty unimpressive.

A 100kg person falling 2 metres without any protection can experience impact forces of over 15 Kn (KiloNewton) when they hit the ground or an obstruction. In all its fragility, the human body cannot absorb this impact. As a result, bones, organs, muscle and tissue will disintegrate. A properly fitted harness with height safety equipment reduces fall impact to below 6kN, thus avoiding long-term injury. This article identifies some factors that affect safety at height, and discusses ways you can improve it in your workplace.

Protecting your workforce when they are working at ANY height is a vital obligation and mandated in all Australian states. An approved harness is therefore essential. Fall arrest equipment works by absorbing shocks. For this purpose a snug but comfortable fit is essential. In general, fall arrest equipment is made for people of average weight and height. Workers (both male and female) who are particularly tall, short or heavy will need special consideration.

PREVENTION

The simplest yet most immediately effective way of completing any work task is to work on the ground – an obvious safe choice! Secondly, working under the principles of restraint is far better than the next choice of fall arrest. Restraint is where a worker’s system will not allow a fall from height. The need to work in a fall arrest situation is a very serious responsibility. It is important to remember when working at height, it is mandated that all workers wear appropriate height safety equipment in accordance with a risk assessment and a rescue plan.

When using a fall arrest device, the shock absorbing component ( lanyard) must be rated and Australian Standards approved to 15 Kn for a single person and 21 Kn for two. A typical 2 metre lanyard, in a 2 metre free fall can extend under the load of a 100kg wearer to 1.75 metres as it arrests the fall. This simplified fact is the first step in calculating fall clearance – ie. knowing all of the measurements that make up a distance that prevents a “ground strike”. And here’s an important tip: heavier workers may stretch the lanyard further, potentially allowing them to strike the ground or an obstruction – you must make sure that the lanyards you supply are appropriate to the weight of the workers they are protecting.

Harnesses – There are numerous “fit for purpose” full body harnesses, but it’s important that in each type selected, correct personal fit is the primary focus. It MUST fit correctly, so that fall loads are taken up smoothly, without shock, and the wearer is not injured by the restraint. Your supplier MUST advise you on the correct type and size of harnesses for your workforce and workplace.

Self-Retracting Lifelines – Where a compliant overhead anchor and anchorage is available, and where any fall is likely to be vertical, a Self-Retracting Lifeline is preferable to a simple shock absorbing lanyard. The problem with shock absorbing lanyards is that they will not begin their work until the slack is taken up, which means the worker could have fallen 1 – 1.5 metres before deceleration begins. A SRL, by contrast, arrests the fall as soon as the line exceeds a set speed and load, engaging the built in inertia clutch. SLRs are generally rated up to 163kgs, making them adequate for most workers. REMEMBER to add up the worker’s tools, gear and boots. SLRs must not be used in circumstances, such as working on a pitched roof, where a sloped surface fall is likely to prevent the operation of the inertia mechanism. Your supplier MUST be able to advise you on the best system for your needs.

Anchoring fall arrest equipment –Any restraint or fall arrest system is only as good as the point to which it is anchored. Anchors and anchorage points should be designated by someone with the expertise to determine their adequacy for the purpose – ie. to remain intact during severe fall loads. Some well-meaning people in the past have secured a well-designed, compliant, load rated eye bolt (anchor) into a single brick wall (anchorage)!

RESCUE

Protecting your workers from injuring themselves in a fall is of course vital, but it’s only the first part of the story. You MUST have a comprehensive rescue plan in place before you undertake any work at height.

As a general principle, a good rescue plan should, where possible, start at ground level and work up. Self-rescue should be possible whenever a worker may be working at height unaccompanied. Don’t rely on the mobile phone as your rescue plan; what happens if it falls or gets damaged during your fall?

Keep it Simple in Rescue – In the first instance, simple devices like ladders and man-lifts should be available in sufficient numbers. However, whenever a mechanical lifting system is used, it should be designed to accommodate a restraint or fall arrest device.

Recovery – Workers who have been suspended for extended periods in a harness without obvious injury may have suffered circulatory damage – notably pooling of blood in the legs. Any worker rescued from such a situation should receive prompt medical attention, as recommended by The Australian Resuscitation Council Guidelines. You can learn more at www.resus.org.au.

SafetyQuip is a leading supplier of Height Safety equipment in the Australian marketplace and can assist you with advice and selection on any of the devices referred to in this article. The SafetyQuip team includes trained sales specialists who can advise you on the most suitable equipment including harnesses, lanyards, self-retracting lifelines, and other height safety equipment. We also supply height safety and rescue kits. For more info, contact your nearest SafetyQuip store.