Minimum Clearance Distance in Fall Arrest Systems with Energy Absorber Lanyards

Abstract

Accidents due to falls from height are one of the main causes of death in workplaces. Fall arrest systems (FAS) are designed to arrest the fall safely without injuring the accident victim. Their main mission is to restrain the body so as to prevent it from hitting the ground, generating forces and accelerations in the arrest process that are not harmful. A lack of empirical evidence and scant technical information provided by manufacturers regarding minimum clearance distance (MCD) below anchorage makes it necessary to study the safety distances required in the use of Energy Absorber Lanyards (EAL). This paper aims to determine the MCD below anchorage to arrest a fall using an EAL without hitting the ground. The real deformation of EAL when stopping a fall is studied. Ten EAL models distributed internationally by six manufacturers were chosen. Dynamic behavior tests were performed on the samples. Using image processing the total elongation of the equipment (elastic plus plastic) is obtained. The main conclusions are that maximum plastic elongation could be reduced by 29%. The method described in EN 355: 2002 underestimates elongation by up to 70% for some equipment 20% of EAL’s exceed the maximum arrest force (Fm) allowed in EN 355. The MCD data provided by manufacturers is not reliable. The data provided by manufacturers are incomplete. It is recommended that quality control for EAL’s be strengthened to ensure that products launched onto the market meet the requirement of EN355. The findings of this study recommended increasing MCD distance longer than that calculated according to EN355, at less than 1 m.

Determining the Safest Anchoring Knot in a Fall Arrest System by Means of Static Tests

“…All ropes were made from synthetic textile fibres and consisted of a braided core and sheath with a low elongation coefficient. These are the types of ropes used in RASs [10,12,[25][26][27]29,41,57]. The range of diameters was between 10.5 and 11 mm, which is the range commonly used in RASs and allows for a reliable comparison of results.…”

“…The overhand sling, figure eight sling, figure nine sling, clove hitch, and double overhand sling are anchoring knots. These knots are used in rope access systems in the construction sector for the maintenance of skyscrapers, power pylons, dams, and unique high-rise projects [10][11][12][25][26][27][28][29].…”

Study on the pressure distribution of fall arrest belts in the static suspension and falling process

“…1,2 Unfortunately, accidents due to falls from height remain one of the leading causes. 3,4 According to a survey in Australia, FFH at workplaces was one of the major causes of injuries, with a fatality rate of 14%. 5 FFH is also the cause of the most significant number of deaths in the USA, especially for construction fatalities (about 36.9%).…”

“…2,6 Furthermore, FFH accounted for 42.3% of serious and 25% of fatal accidents in Spain. 4 A total of 5379 falls from height were reported, 70 of which led to severe injury and 38 to death, just in 2017 in Poland. 6 The use of personal protective equipment, including safety seat belts, is one of the primary methods of protection against falls.…”

“…2,6 Furthermore, FFH accounted for 42.3% of serious and 25% of fatal accidents in Spain. 4 A total of 5379 falls from height were reported, 70 of which led to severe injury and 38 to death, just in 2017 in Poland. 6…”