White paper

Fit for Purpose Product Testing

Constant Force® post system & Performance
Introduction
Checklist
Over the last fifteen years, Latchways has pioneered
Constant Force technology
the advent of ‘top fixed’ systems incorporating their
Representative roof test
patented Constant Force® post technology and ManSafe®
componentry. ‘Top fixed’ refers to the fall protection Roofing system manufacturer approval
being installed to the complete roofing system rather than 300 kg dynamic drop test
the traditional method of attaching an anchor through the Multi-directional testing
roof to the building structure. Omni-directional post
With such a fundamental change to the method of load control and 6000J energy capacity per post
attachment, combined with the proliferation of copy-cat products
Three user unrestricted system
available on the market, it is imperative that specifiers, contractors,
clients and end users can be confident that the selected product is EN 365 product marking
‘fit for purpose’. Foreseeable misuse
In order to do so, Latchways undertake a rigorous two-stage
testing programme in conjunction with major roofing system partner
Traditional ‘through Constant Force
manufacturers. As a result, Latchways are able to provide an the roof’ post ‘top fixed’ post
unrivalled product portfolio with proven performance in excess
of the minimum standards.

This document sets out to explain the testing programme behind

the ManSafe for Roofing Constant Force post system and how
Latchways determine the correct specification of Constant Force
post for a given roof construction. The following pages provide a full
explanation to assist the decision making process, due diligence,
liability and ensure compliance.

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 Fall protection standard Omni-directional post
The standard governing the testing of anchor EN 300
kg
To ensure maximum protection for users, each post
devices is EN 795 and should be considered as
the absolute minimum requirement. Systems are
incorporates the Latchways unique omni-directional
Constant Force energy absorber, enabling the post
✔
categorised within this standard as either being to deploy and control load in any direction.
class A1, A2, B, C, D or E. The classes pertinent
to the Constant Force post are A2 (isolated
anchor devices) and C (anchor devices employing
horizontal flexible lines).
Under the standard, anchor devices are tested by
6000J energy
subjecting them to a dynamic test using a 100 kg capacity post
mass — the equivalent of one person falling. To ensure that the loads to the roof are maintained EN516
The Latchways Constant Force post exceeds to 10 kN, each Constant Force post has the
this standard.
✔capacity to absorb at least 6000J of energy.

100
100
100
kg
kg
kg =
= 300
300 =
=

EN 795 test ✔
kg
kg
100%

Representative roof test Three user unrestricted

100%
Latchways undertake extensive testing of complete system 300
kg

and representative (6 m x 6 m) roofing systems. 100%stated, and with the exception of

EN516 Unless otherwise
These take into consideration the supporting single point anchors, the Constant Force post system
structure such as purlins, decks, spacer system, is suitable for access by up to three users at any one
insulation and outer waterproofing covering. time and at any point along the length of the system,
even between two anchors.

EN516 100%
Roofing system
manufacturer approval
Latchways partner with industry-leading
manufacturers to ensure a holistic approach.
Latchways are therefore able to provide solutions
✔
for new roofing system innovation and ensure latest
legislation is met. In addition, Latchways Mansafe 3 users unrestricted access
solutions maintain the guarantees/warranties 100%
offered by partner manufacturers.

300 kg dynamic drop test

✔ EN 365 product marking
300
kg
Latchways conduct this test using a 300 kg mass The Latchways CFP is labelled in accordance with
(the equivalent of three users) dropped through a EN 365 standard.
100% EN516 100%
distance of 1.5 m, on one post connected to the
roofing system.This mass is 3 times the standard
of 100 kg required by EN 795.

300 EN516 100%

= = Foreseeable misuse
kg
Best practice dictates that the system layout be
Latchways test designed in fall restraint, however, Latchways also
take into consideration foreseeable misuse of their
300
products; for example, use of an incorrect lanyardkg

length. In certain cases there may also be a

Multi-directional testing
requirement to utilise the fall protection system
1 In line with the seam, profile or deck for carrying out rescue following a fall. Therefore,
the anchor device should always be capable of
2 Across the seam, profile or deck
300
controlling multi-user fall arrest loads irrespective
3 At 45º to the seam, profile or deck kg
of the system classification.
(static load only)

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Constant Force technology Multi-directional testing
At the heart of every Constant Force post is the unique Latchways 1 In line with the seam, profile or deck
energy absorbing coil. 2 Across the seam, profile or deck
3 At 45º to the seam, profile or deck (static load only)

Single Constant Force post

Inline with Across

the seam the seam

45° to seam

Multi-directional testing on 6 m x 6 m roof sample

To ensure maximum protection for users, each post incorporates the

Latchways unique omni-directional Constant Force energy absorber
enabling the post to deploy and control load in any direction.

Under load the post deploys over, extending the energy absorbing coil
whilst, at the same time, limiting the load to the roof to a typical peak
of 10 kN (1 tonne) in shear.

Testing programme
Dynamic drop test—Stage 1
This is the most revealing test for any ‘top fixed’ post/roof
construction and in the case of Latchways is conducted using a
300 kg mass (the equivalent of three users) dropped through a
distance of 1.5 m, on one post connected to the roofing system.

Only when these tests have been successfully conducted, i.e. the
test mass was arrested whilst maintaining the integrity of the roof
at a typical peak load of 10 kN, will the solution be deemed to
have passed. At this stage the Constant Force post system can
be installed to the given roof construction in a restraint application,
300 allowing for foreseeable misuse or using the system to undertake
kg rescue following a fall.

Energy absorption comparison

Potential energy
1.5 4,415 Joules To further underline the performance of Constant Force technology, a
metres comparison can be drawn in terms of the potential energy absorption
of the Latchways Constant Force post compared to a basic EN 795
rated anchor device.

Typical 10 kN
Energy input=
peak load
Mass (kg) x Gravitational Acceleration (m/s2) x Height (m)
to roof
Latchways Latchways test
300 x 9.81 x 1.5 = = 4,415 Joules

EN 795 EN 795 test

300 kg dynamic drop test
100 x 9.81 x 1.5 = = 1,472 Joules

It is important to note that EN 795 only requires the use of a 100 kg The Latchways Constant Force post has three times the energy
mass (the equivalent of one user) dropped on an anchor device. absorbing capability compared to an EN 795-rated anchor.

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Static load test—Stage 2 Fall restraint or fall arrest
For Latchways to determine an appropriate Factor of Safety, each (including foreseeable misuse)
Stage 1 test is subject to a static load held for a given period of time. Fall arrest is defined as allowing the worker ’exposure’ to the
Where a Factor of Safety of 2 is required, the whole construction, hazard i.e. they can get to the edge of a roof and potentially fall,
including the Constant Force post must be able to withstand a static whereas fall restraint allows the worker access towards the roof
load equivalent to twice the working load achieved during Stage 1. edge but no further.
In the case of the Constant Force post, 10 kN must be increased to The Latchways Constant Force Post is suitable for both fall restraint
20 kN, held for three minutes, with no failure of the complete system. and fall arrest applications and therefore allows for forseeable
When all Stage 1 and Stage 2 tests300 have been successfully misuse of the system.
kg
conducted the Constant Force post can be installed in a fall arrest
application to the given roof construction. Please note that
fall arrest applications are only permissible where a sufficient fall Solution:
clearance is present. Fall restraint

3 users Factor of Safety 3 mins

working load static load
10 kN 20 kN

Product marking No lanyard

adjustment required
(perimeter system)
In accordance with EN 365 the anchor device must display
Training requirement:
the following information: Basic
1 Means of identification, e.g. manufacturer’s name,
supplier’s name, or trademark
2 Manufacturer’s production batch or serial number Solution:
or other means of traceability Fall arrest
3 Model and type/identification
4 Number and year of the document to which the
equipment conforms

5 Pictogram or other method to indicate the necessity

for users to read the instructions for use

Lanyard adjustment
required (ridge system
with anti-pendulum posts)
Training requirement:
Advanced

Registered installers
As a key element within the Latchways supply chain, only registered
Latchways installers are permitted to install ManSafe products.
Such companies are fully trained and able to offer a complete
service package to the customer including initial design advice,
pricing, installation, maintenance and the correct future annual
inspection and recertification of systems.
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1
3
2

Further information
For more detailed product information, copies of test
reports and manufacturer approval letters please contact
info@latchways.com

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ManSafe® and Constant Force® are registered trademarks of Latchways plc

Latchways plc, Hopton Park, Devizes, Wiltshire, SN10 2JP, England

Tel: +44 (0)1380 732700 Fax: +44 (0)1380 732701
Email: info@latchways.com Website: www.latchways.com

13A-V2-06/11