EN 354:2010 -Lanyards for Fall Arrest
EN 354:2010 – lanyards for
fall arrest
Considering the changes introduced by the publication of EN354:2010 and
its effects on the testing of fall arrest lanyards.
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Lanyards are a common component of the fall protection system for
operatives working at height, with a variety of designs, lengths, materials and
configurations possible. During use, they are exposed to hazardous wear and
tear, so rigorous testing is necessary. The new standard increases the amount
of testing required to ensure that CE-marked lanyards are fit for purpose.
Scope
The scope of EN 354 has increased to now explicitly include work
positioning and restraint lanyards, as well as lanyards with multiple
configurations such as twin-tailed models. This means that products such as
work positioning lanyards are now covered under the scope of both EN 354:2010
and EN 358:1999. EN 354:2010 has not superseded EN 358:1999, which means there
is an ambiguity in which standard products should be certified to, due to difference
in the requirements of the static strength and dynamic strength tests.
A range of options to clarify this situation is being discussed at
various levels of national and international committees. These choices range
from clarifying the scopes of EN 354 and EN 358 to moving lanyards out of EN
358 completely. SATRA will currently test lanyards to either EN 354:2010 or EN
358:1999, using the intended end-use of the product to determine the most
appropriate standard.
Conditioning
This standard is one of the first fall arrest standards to bring in
specific conditioning requirements for samples. All test samples are now
required to be conditioned at 23oC ±5oC and 65 per cent ±
5 per cent relative humidity (RH) for at least 24 hours prior to testing.
In addition to this general conditioning, two more pre-test conditions
have been introduced: ‘wet and cold’ and ‘very cold’. The wet and cold
condition applies to all lanyards being tested to EN 354:2010, while the very
cold condition is an optional test designed for lanyards for use in extreme
cold environments below -30oC.
The wet and cold conditioning is used for samples being tested for
static strength and slippage tests. To prepare a sample, it is completely
submerged in water for one hour. Afterwards, it is placed in a climate chamber
with a temperature set to between -4oC and -6oC (a range
of -4oC to -8oC being acceptable) for at least four
hours. Samples are then removed and tested, which must start within 90 seconds
of removal from the freezer.
The conditioning to very cold is different to wet and cold in more than
just temperature, as the lanyard is not soaked in water. After general
conditioning of 23oC ±5oC and 65 per cent ±5 per cent RH,
the sample is placed in a freezer set to the minimum temperature claimed by the
manufacturer, with a maximum of -30oC for at least two hours before
removal and testing.
This new conditioning may present the largest changes in the new
standard, as well as the biggest problem for manufacturers. Textile lanyards
containing nylon will become weaker due to the conditioning prior to testing.
This is because of the ice melting as the test is being conducted, so releasing
water into the lanyard. The water acts as a plasticiser on the nylon, thus
lowering the tensile strength of the lanyard. This will reduce the maximum
force the lanyard can hold, possibly resulting in failure. As the uptake of
moisture into the core of a nylon lanyard is a major problem, water-resistant
coatings will take on a greater importance.
Slippage
EN 354:2010 now includes an adjustable lanyard slippage test. This is a
similar test to the one found in EN 358:1999. The adjustment device is placed
at the mid-length position and a static load of 6kN is applied for three
minutes. To pass this test, the adjustment device must not slip by more than
50mm. This test is carried out two or three times (depending on the conditions
claimed), first using the general conditioning of 23oC ±5oC
and 65 per cent ±5 per cent RH, and then to a sample conditioned to wet and cold.
A second sample can be used for this test. If a manufacturer is claiming the
very cold performance rating, this test is repeated again to this conditioning.
Static strength
Static strength
testing of lanyard
In use, lanyards can be subject to some of the highest levels of wear
and tear in a fall arrest system. Lanyards can abrade against edges and other
obstacles, as well as being exposed to adverse weather conditions and UV light.
It is due to these adverse conditions that the standard retains the 22kN
static strength requirement for textile lanyards from the 2002 edition. This is
above the standard 2.5 times safety factor used in most fall arrest standards.
Lanyards constructed entirely from metal are subjected to a 15kN static
strength test, as they are more resilient to wear and tear. Lanyards terminated
with connectors have the connectors removed for the static strength tests. The
connectors are still included in the corrosion test.
The conditioning required for static strength is subject to some
ambiguity. The standard clearly states the conditioning sub-clauses that are
required in the slippage testing. In the static strength test, the standard
only states when conditioned to the main conditioning clause of 5.2, with no
clarification of which sub-clauses to apply.
At SATRA, we have set out to test the lanyards to all the applicable
sub-clauses. This ensures that the product is rigorously tested to prove its
performance.
Test methods for twin-tail lanyards are now included. Any multi-leg
lanyard is required to be tested in all possible configurations to a force of
22kN (textile) and 15kN (metal). Each configuration is tested under all the
applicable conditioning.
Dynamic
Lanyards which include a length adjustment device are subjected to a
dynamic strength test. This test differs from previous test methods for
adjustable lanyards. A 100kg test mass is attached to the test sample via a 2m
reference lanyard. The mass is raised 2m above the attachment point, giving a
free-fall distance of 4m. To pass this test, the lanyard must retain the test
mass clear of the ground. There is no requirement for measuring the forces
generated.
After the dynamic test, a 3kN static strength test is performed on the
adjustment device to test the lanyard’s residual strength. If the lanyard can
withstand this force for three minutes after the mass is dropped, it is
considered to have met the requirements.
Corrosion
The corrosion testing of the metallic components is now assessed by a
48-hour exposure time, compared to the previous 24-hour corrosion test. The
extra exposure to the neutral salt spray can lead to failures of metallic
components that are already used on products which only required 24-hour
exposure. This longer test may require a change of coating on the metallic components
in order to meet the new requirements.
Product marking
Product marking requirements now mean the length of the lanyard and the
date of manufacture are needed on the lanyard itself. Information regarding the
pictogram, model/type and marking has now been moved to a different standard
(EN 365).
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