ARRESTING FORCES THROUGH ENERGY ABSORBER

ARRESTING FORCES THROUGH ENERGY ABSORBER Regarding the design action, quoting EN 795:2012 point 7.b: “The user shall be equipped with a means of limiting the maximum dynamic forces exerted on the user during the arrest of a fall to a maximum of 6 kN”. This requirement is also reported in all product manuals, therefore we consider this value as the design load for the calculation. Observing real life situations has confirmed that, with the use of energy absorbers, retractable devices or guided-type fall protection, devices show an arresting force between approximately 4 and 4,5 kN.

[kN] 4

3 2 1 0

ITALIAN STANDARDS UNI EN 355:2003

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Test 100/F/1m progress of F (kN) relative to time t (s)

UNI EN 355:2003 establishes that in experimental tests, the braking force Fmcs necessary to stop a 100kg bodyweight mass in free fall from a heigh equal to 4m (hcl) must not exceed 6 kN, and the arresting distance must be:

[kN] 4

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arresting distance < (2Lt + 1,75 m)

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where: 1

Lt = total length of the energy absorber (including rope) h1 = attachment point distance - ground before the fall h2 = attachment point distance - ground after the fall hcf = h1 - h2 = braking length

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Test 100/F/2m progress of F (kN) relative to time t (s) [kN] 4

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Test 100/F/3m progress of F (kN) relative to time t (s) [kN]

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hcf h1

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Test 100/F/4m progress of F (kN) relative to time t (s)

8 | ARRESTING FORCES THROUGH ENERGY ABSORBER | FALL PROTECTION SYSTEMS

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FALL PROTECTION AND SAFETY - EN

RELIABILITY CERTIFIED As the manufacturer, Rothoblaas is responsible for certifying its products. All the products documentation (certifica...

FALL PROTECTION AND SAFETY - EN

RELIABILITY CERTIFIED As the manufacturer, Rothoblaas is responsible for certifying its products. All the products documentation (certifica...