Aspiring Enterprises


An outline of fall-protection for workers at height and their employers.


This article is not an instruction manual, and should not be considered a substitute for competent instruction.

Contact us for referral to a qualified training organisation.


  1. The risks of work at height

  2. Legal considerations    

  3. The hierarchy of control    

  4. Fall protection    

  5. Restraint systems    

  6. Work-positioning systems    

  7. Fall arrest systems    

  8. Connector safety    

  9. Drop-lines and rope grabs    

  10. Retracting lanyards and lifelines    

  11. Horizontal life-lines    

  12. Anchorages    

  13. Fall clearance      

  14. Swing-fall hazards    

  15. Elevated work platforms    

  16. Roof work    

  17. Suspension trauma and rescue    

  18. Equipment maintenance    


In the construction industry, falls from height are the most common cause of fatal workplace accidents. Falling is also a hazard in other industries such as telecommunications, electricity reticulation, and building maintenance.

Several people die in New Zealand each year as a result of falling from height at worksites. Usually a fatality is due to total lack of a fall protection system, even though it is required by law and by common sense. Very rarely, it is due to failure of a fall protection system through misuse.

Proper hazard management must be in place to manage the risks of working at height. Fall protection is a planned response to foresee-able fall hazards. A fall protection system is established when a hazard assessment has identified a risk of falling.

A hazard assessment should be made at each work site, documenting the potential hazards, the likelihood and the severity of the risks associated with them, and the steps taken to deal with them, normally by using a hierarchy of control analysis. See section 3 for an explanation of this concept.

The hazard assessment should consider "access to and egress from the work area, ability of work platforms to support people and equipment, size of and changes to the work platforms, restraints to stop people stepping off work platforms, obstructions caused by materials and objects, unprotected work platform edges or openings, and proximity of energy sources such as electricity and gas" (OSH Guidelines for the prevention of falls).

Decisions on the appropriate fall protection system should be based on a careful assessment of the work site. The need for training of all staff must also be taken in account.


Under the Health and Safety in Employment Act 1992 and the Health and Safety in Employment Regulations 1995, employers and their workers are required to take "all practicable steps" to eliminate, isolate, and minimise work-place hazards. Workers who risk a fall of three metres or more must be supplied with fall protection. Any work risking a fall from five metres or higher must be notified to OSH.

OSH often stops work on sites where fall protection guidelines are not being observed, and can prosecute employers for failing to protect employees from work-place hazards.

Apart from the general requirements of the HSE Act, there are specific industry obligations, as set out in the OSH "Guidelines For The Prevention Of Falls", which employers are required to observe.

Further guidance is available from the recent standard AS/NZS 1891.4:2000, Industrial fall-arrest systems: Part 4: Selection, Use, and Maintenance. Compliance with the requirements of this standard and the OSH Guidelines is obviously necessary, though in itself this does not confer immunity from prosecution. Therefore, expert advice may be required, and a height safety consultant should be engaged for major projects.

There is also the possibility of a civil prosecution, as shown in Australia by the 2001 award in the NSW Supreme Court of an $11.2 million settlement against various defendants, including the employer of the plaintiff, after he became quadriplegic in a fall from a cherry picker.

Employers, manufacturers, and suppliers also have a "duty of care" extending to eliminating foreseeable hazards. "By being reluctant to point out hazards, principals and others are failing to meet the responsibilities of the HSE Act and Regulations" (OSH Guidelines).


The hierarchy of control is a method of hazard management for the worksite. The concept is that higher-level methods are always preferred over lower-level methods. The hierarchy of control for fall hazards is as below:

Elimination: This means the work is performed by a different means which does not expose the worker to the fall hazard. For example, it may be possible to fabricate items on the ground rather than assembling them at height.

Isolation: This requires barriers or other means to prevent workers reaching the fall hazard area. In particular, "penetrations" through a floor can be fenced off. Edge protection on the perimeter of a roof is being required more often.

Protection: This requires a fall protection system, including a harness, which either prevents a fall from occurring, or ensures that if a fall does occur, the worker will be held in the harness.

This article is concerned only with fall protection systems, which are of three types:

  • Restraint system, which uses fall protection equipment to prevent a worker from reaching a fall hazard, such as the edge of a roof
  • Work-positioning system, which supports a worker directly with fall-arrest equipment so that there is little chance of a fall, and in the event that a fall does occur it will be minor
  • Fall-arrest system, which is designed to stop a fall without injury to the person falling

In the list of fall protection systems above, the most preferred system is again at the top.


Prevention of a fall can be achieved by use of a restraint system, which ensures that a worker cannot reach a position where a fall could occur. For example on the flat roof of a commercial building, the system might comprise a central anchorage on the roof, harnesses for the workers, and ropes connected to the harnesses. If the rope is shorter than the distance to the edge of the roof, then this is a restraint system.

Because no fall can occur, the strength requirements are lower for this type of system.

If a fall might occur a fall-arrest system must be used, and the equipment provided has to be capable of holding the impact of such a fall. See section 7.

A third type of system, intermediate between these two, is a work-positioning system. This arises when a worker is suspended in a harness, such as on a power pole. See section 6.

Any fall protection system always requires three elements:
  • A suitable harness
  • An anchorage capable of sustaining any applied load
  • The means of connecting the two together

The connection part of the system can include a lanyard (which must include a personal energy absorber if it is used in a fall-arrest system), a rope and rope grab, and connectors such as karabiners and snap-hooks.

Under the hierarchy of control, the elimination of fall hazards is the preferred approach, so the prevention of a fall by using a restraint system is the preferred method of working wherever possible. The order of preference of fall protection systems is therefore as below:

1. Restraint system
2. Work-positioning system
3. Fall-arrest system

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There is no such thing as a "safe fall", or a "safe fall distance", because the outcome of a fall is always unpredictable. There are numerous possible hazards in a fall, including:
  • Impact with a protruding object
  • Whiplash injuries
  • Internal injuries due to sudden deceleration
  • Adverse effects (including death!) of hanging in a harness too long (see section 17)
  • The possibility of a swing fall to impact an adjacent wall or object (see section 14)
  • Failure of a component in the fall-arrest system

Because of these uncontrollable hazards, falls should be considered a major risk even if a proper fall-arrest system is used. Therefore a fall prevention system (also known as a restraint system) must be used whenever possible to eliminate the chance of a fall - bearing in mind that "all practicable steps" should have already been taken to isolate the workers from the hazard.

As defined in AS/NZS 1891.4:2000 Industrial fall arrest systems devices, Selection use and maintenance, the total restraint system requires "a combination of anchorage placement and lanyard/line length which will not physically permit the operator to reach a fall-risk position." Typically this system is used on the roof areas of commercial buildings. The worker wears a harness connected to a rope, which is attached to an anchor or anchors in such a configuration that the worker cannot reach the edge of the roof. There may be a single anchor in the centre of the roof, or two anchors at different positions. The harness for a restraint system can be either a fall-arrest harness or a work-positioning harness. The advantage of the fall-arrest harness is that it can also be used if the system is later changed to fall-arrest.


A work-positioning system is used when a worker is suspended on a rope. Examples are:
  • A rope access system (in which the worker abseils down the side of a building)
  • Work on a sloping roof
  • Pole work performed by electrical workers
  • Work on broadcast and power transmission towers in which the worker is suspended from the structure
  • Tree surgery

Work-positioning systems are considered to be higher than fall-arrest systems in the hierarchy of control, because the risks of a fall, with its uncertain consequences, are avoided, as the worker is already partially or completely hanging in suspension.

Rope access is a specialised activity which requires specific training and is not within the scope of this booklet.

A work-positioning system can only be justified if any fall that might occur is a limited free fall, meaning that it cannot be greater than 600 mm. A work positioning harness may have attachment points as for a fall-arrest harness, or an attachment point at the front of the waist, or a pair of attachment points on the hips for attachment to a pole strap, as used by electrical workers.

At present it is permitted to perform pole work with a waist belt only, but it is likely that in future versions of the harness standard only harnesses (incorporating leg loops) will be permitted.

Climbing fixed ladders with a drop line is not strictly work-positioning, but a work-positioning harness can be used provided the system does not allow a fall of over 600 mm. See section 9.

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A fall-arrest system requires a fall-arrest harness, incorporating a high-level attachment point, which can be either in a frontal position at the chest, or in a "dorsal" position between the shoulder blades. The harness must be the correct size and be adjusted securely. The harness instructions must be followed carefully to ensure the correct use of the harness. To comply with the New Zealand standard, AS/NZS 1891.1:1995, the attachment point must be labelled as a fall-arrest attachment point. The harness may have other attachment points also.

Fall-arrest systems are designed to limit the impact of a fall to no more than 6 kN force. This is the force generated by a 100 kg person accelerating or decelerating at 6 times the force of gravity, or 6G. As falls of only 600 mm can generate forces in excess of 12 kN, it is essential that a personal energy absorber is used in a fall-arrest system. This is a one-use device that tears out in the event of an impact, and absorbs energy to limit the peak impact load to a maximum of 6 kN.

The personal energy absorber is usually built in to a lanyard, and the combination of the personal energy absorber and lanyard is called a lanyard assembly, and is typically two metres long overall. In the simplest case a fall-arrest system comprises just a fall-arrest harness and a lanyard assembly, connected to a suitable anchorage with a strength of 15 kN. However, where more mobility is required, the system complexity increases. In vertical work, such as on ladders and towers, vertical ropes called drop lines may be fitted to the structure. See section 9. Alternatively, retracting life-lines (fall-arrest blocks) with webbing or wire cable may be used.

When horizontal movement is required, anchor ropes may be required to connect to remote anchorages, or horizontal life-lines may be installed - see section 11.


Obviously it is vitally important that the lanyard assembly and the harness are connected together, and remain so. Often connection is made by a double-locking snap-hook; however some of the available snaphooks can be easily disconnected from the harness by twisting the gate of the hook against the harness D-ring, while applying gentle pressure on the safety latch, thereby causing "roll-out" of the snap-hook from the D-ring.

Because most common connectors, including various types of karabiners and snap-hooks, can in some conceivable circumstances be disconnected from a harness, we supply Maillons Rapides, also called screw-links, quick-links, or tube-nut connectors, as standard fittings on the harness end of our lanyards. At the anchorage end of a lanyard there is less chance of roll-out because the anchor eyes are usually too small, or may be flexible (eg webbing slings).

The snap-hooks supplied on Aspiring lanyards are a forged steel type and pass our simple "table test" for snap-hook safety, which can be applied to all snap-hooks having the safety latch on the back of the snap-hook opposite the gate and parallel, so that the gate can be opened by squeezing the gate and the latch towards each other. The snap-hook is placed on its back on a table under downward pressure, and then pressure is applied to the gate. If the gate opens (because the latch is already depressed), the snap-hook fails the test. Such a snap-hook has a greater chance of roll-out from a D-ring.

Karabiners, which are a D-shaped ring with a spring gate, are also used as connectors. These come with screw-locking, twist-locking, or triple-locking mechanisms. Triple-lock karabiners require the least care in use and are the safest option, provided the locking mechanism operates properly. However this type of mechanism is prone to failure. If the sleeve does not close properly they must be discarded. Twist-lock karabiners are used for anchor connections, but should not be used at the harness end of a lanyard. Screw-lock karabiners require care to ensure that the screw sleeve on the gate remains screwed up.

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" Drop lines" are vertically-oriented ropes used to protect workers climbing fixed ladders on structures. The worker uses a rope grab, a device which moves up and down the rope The rope grab is best connected directly to the harness with a karabiner or screw-link.

Though standard rear-attachment point harnesses are often used, drop-lines suit a front-attachment harness better. Furthermore, because the potential fall distance can be restricted to no more than 600 mm ( a "limited free-fall"), a full-body fall-arrest harness is not required and a work-positioning harness can be used.
Various types of device are available, but for drop lines a rope grab such as the CT Rope Grab is best suited, as it runs freely both up and down the rope. This is a compact stainless steel unit which is designed to grip tenaciously on the rope with minimum slippage. It is easy to fit to the rope and cannot be detached while fitted with a connector. Rope grabs should comply with EN 353-2.

Anchor ropes are ropes which are rigged essentially horizontally, typically on the roof of a commercial building to secure workers performing maintenance under a restraint system. The ropes are fixed to an anchorage using a secure knot, such as a figure 8 loop. The rope is often connected to the harness with a rope grab, though it can also knotted and connected using a karabiner. Generally there should be two ropes, anchored at different points, to avoid the swing-fall effect described on page 16. Alternatively, if a fall-arrest system is required, a lanyard assembly is connected to the second anchorage.

The ropes used for drop lines and anchor ropes should be 11mm kernmantel (core-and-sheath braid) low-stretch ropes, complying with either the AS 4142.3 (Australian) or NFPA 1983 (American) standard for rescue ropes. Three-strand laid (twisted) ropes are of lesser quality, and should be replaced with modern kernmantel ropes, which are much more durable and reliable.


Retracting life-lines (also called fall-arrest blocks, inertia reels, or fall arrest devices) offer the best protection to a worker in a fall-arrest situation because the webbing or cable retracts to the minimum amount automatically, thereby ensuring the shortest possible fall. If fall clearances are small (see section 13), there may not be enough clearance for a lanyard assembly incorporating a personal energy absorber, as these extend by up to 1.75 metres.
Retracting life-lines are particularly suitable for two situations: repetitive work in a vertical zone, such as up and down a fixed ladder, and on horizontal life-lines (see section 11). Other situations should be treated with caution, because the length of webbing or cable which is sometimes available can allow a major swing fall (see section 14). The shorter retracting life-lines are inherently safer because of this.

Some retracting life-lines may not operate properly outside of a cone of about 30 degrees from the vertical. Also, at greater angles the effect of a swing fall will be greater.

Retracting life-lines will not function correctly if the impact on the line is not sufficient to activate the locking mechanism. This may happen if a worker falls into grain in a grain silo, as the line can continue to fed out without locking because there is no impact on the reel. It can also happen if there is friction of the line running over an edge, or on slopes because a person rolling down an incline may not generate enough inertia to lock the reel. Both these effects apply on roofs, and each alone is a good reason for not using retracting life-lines on a roof.

Generally these devices are designed to be used for falls of up to 600 mm vertically, so the work situation needs to be analysed carefully to ensure that greater falls do not occur. Essentially this means that anchorages must be above head height.

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Horizontal life-lines (also called "static lines") are lengths of rope or wire cable rigged horizontally along a structure, and used as a long horizontal anchorage, connected to the worker with a lanyard that travels along the line following the worker's movements. They may be up to 100 metres long, and have intermediate anchorages to divide them into spans.

Horizontal life-lines offer great freedom of movement; however there are several pit-falls in their use. Firstly, access to the life-line must be made safe. Secondly, provision must be made for passing from one span to the next without disconnecting from the system, usually by using a twin-tail or double lanyard.

Because of the physics of horizontal lines, it is possible to impose extremely high loads on them, with the load increasing the more the line is tensioned. Therefore the engineering of horizontal life-lines is a complex matter. Long-term life-lines are constructed from wire cable, which can be rigged with a 5% sag (i.e. 500 mm per ten metres), to avoid excessive tension. With this amount of sag the load imposed on the anchorages will be five times the load applied, which should not exceed 6 kN if an energy-absorbing lanyard is used. This will impose a maximum load of 30 kN at the anchorage, giving a minimum safety factor of nearly 1.5, for a 10 mm wire cable having a strength of 44 kN.

For short-term life-lines a rope system can be used, providing it is rigged with a strength of 40 kN and tensioned so that a load of 6 kN does not impose more than 20 kN load on the end anchorages. The use of horizontal life-lines presupposes that anchorages can be found with a strength in the range of 40-44 kN. This is difficult to achieve on many structures, and particularly on roofs, except for steel-framed buildings. In general the rigging of horizontal life-lines is a technical matter which is best undertaken by expert riggers.


Anchorages are the third element of the fall-protection system, and are equally as important as the harness and the connection system. Anchorages for fall-arrest must have a minimum strength of 15 kN, and for work-positioning a minimum strength of 12 kN.

For horizontal life-lines, in which multiplication of the applied force can occur, anchorage strength should match the strength of the line, which is 44 kN in the case of 10 mm steel wire.

Anchorages can take a large number of forms, depending on the work site. In many cases an engineering assessment will be required. Often collared eye-bolts are installed in the building. On concrete buildings a simple method is to drill holes and use adhesive to fix the bolts. An alternative is to place expansion bolts (of 12 mm diameter), and then fit eye-nuts to the bolts. In many cases there are suitable structures to which webbing slings can be attached, or sometimes an entire plant room on top of a building can be used as an anchorage by tying a rope around it.

On steel structures anchor points can be fitted by welding steel eyes to the structure. On lattice structures such as broadcast towers and electricity reticulation pylons, the steelwork itself can be used by wrapping webbing slings around the steel members, and also by connecting directly to the structure using a suitably large connecting hook.

Roofs present particular difficulties in obtaining anchors. On commercial buildings with flat roofs there may be guard-rails at the edge of the roof, but often these are not strong enough for anchorages. Pitched roofs present few opportunities for anchoring. There are some commercial roof anchors available, but they are not always practical or cost-effective to use in every situation. Often ground anchors must be used - see the section on roof work.

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A fall at height is never a safe proposition (see section 5). Apart from impact with the ground or major surfaces, there is also the risk of impact with protruding objects. Because of this, the distance to the ground (or a solid object) must not be overestimated. A risk assessment of the site must include an analysis of the distance from the working surface that the worker could potentially fall. To this fall distance should be added a margin of safety to make up the total "fall clearance" distance that is required for certainty that the worker will not impact the ground or a solid object.

In calculating the fall distance the following factors need to be taken into account:

  • Anchorage deflection, which is usually small, but may be up to 1.1 m for a horizontal life-line of under 30 m length prescribed as in AS/NZS 1891.2
  • Static length of the lanyard, which does not usually exceed two metres, but should be shorter if this suits the worksite
  • Extension of the personal energy absorber, which may be as much as 1.75 m, as provided for in AS/NZS 1891.1
  • The height of the worker

A residual allowance of one metre for the safety margin gives the total fall clearance requirement.

In the simplest case a fall clearance of about 6.5 metres is required. With a horizontal life-line this will increase to about 7.5 metres.

If there is rope in the fall-arrest system, the extension of the rope must be taken into account, at around 10% of the length of the rope, and also an allowance for slippage of the rope grab of one metre. For a retracting life-line, an allowance for travel of 1.4 metres is needed.


A provision for fall clearance in itself does not guarantee that a fall will not result in impact with a structure, unless provision is made to ensure that a swing fall does not result in impact with an object to the side of the fall line. An impact from a swing fall (or pendulum fall) can be just as serious as an impact with the ground.
Swing falls are a particular hazard with retracting cable life-lines, because the length of line that is available allows a major swing fall even if the vertical component of the fall is arrested immediately.

To limit swing falls it is important to use anchors as far as possible directly above the work area. If substantial horizontal movement is required, a horizontal life-line is the best solution (see previous section). However, bear in mind that the this gives freedom of movement in only one orientation. Excessive movement at right angles to the life-line may result in a dangerous swing fall.

Another solution is to use two lanyards connected to anchors at different positions. In the case of the self-retracting life-line, it may be possible to use a lanyard connected to a nearby anchorage to counter the swing, or even a rope and rope grab tied to an anchorage opposite the anchorage for the life-line. As the least preferred solution, the anchorage for the life-line might be raised a few metres in order to reduce the angle of the swing.

Generally the use of two anchorages is necessary to eliminate swing falls. Depending on the work-site, it may be possible to use a separate restraint line, or otherwise an anchor rope fitted with a rope grab to allow movement, in conjunction with the main fall-arrest system.

Avoiding swing falls from roofs is covered in the section on roof work (section 16).

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Elevating work platforms include a variety of work platforms, which can be vehicle based, such as cherry pickers, fork-lift platforms, and scissor lifts, or building based, such as building maintenance units (BMUs) and suspended scaffolds. In addition to fall-protection, there are also issues of mechanical maintenance involved in the use of all EWPs for work at height.
In most cases workers using these devices require fall protection, because of the possibility of failure of the vehicle or structure mechanics. Scissor lifts are exempt, because they are not prone to this type of failure.

The bucket of a vehicle-based EWP must be fitted with a secure anchor point, and a fall-protection system usually requires just a fall-arrest harness combined with a medium-length lanyard. The lanyard should be shorter than the standard two-metre length to minimise the potential fall distance, as very little mobility is required within the vehicle's bucket.

The lanyard can be permanently connected to the harness, to reduce the risk of disconnection, although connection with screw-links is also a safe method with no foreseeable way of becoming disconnected.

Because lanyards in cherry pickers can be quite short it may possible to prevent a fall of more than 600 mm occurring in any foreseeable scenario. In this case of "limited free-fall", the lanyard is not required to have an energy absorber. The shorter the fall can be, the less chance there is of tipping the entire vehicle over.

Workers using BMUs and swinging stages require more freedom of movement. A horizontal life-line within the platform could be used if suitably strong anchorages are available on the unit.

(16)     ROOF WORK

Roof work is different from other height safety situations, mainly because the work situation is usually sloping. This adds an element of deception - roofs are more dangerous than they look. Also, it can be very difficult to find suitable anchor points on a sloping roof, unless these have been installed specifically for fall protection.
The ideal set-up for a fall protection system on a typical double-pitch roof uses a horizontal life-line strung along the ridge line, with a rope and rope grab connected to the line and running down the roof. This gives complete freedom of movement across the whole roof. Unfortunately, horizontal life-lines often cannot be used, because they require very strong anchorages (about 40 kN), and many roof structures are not strong enough to have such anchorages installed.

Because of this it is common practice to run ropes from the ground and across the roof, however this leads to the risk of a swing fall (see section 14). This is avoided by rigging anchors at two different points, for example with a rope anchored on both sides of the building.

As this is a work-positioning system, a work-positioning harness can be used, unless there is fragile roofing material, in which case a fall-arrest harness must be used.

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In recent years it has been discovered that people can sometimes suffer severe effects due to loss of circulation while hanging in a harness. This is believed to cause death possibly in as little as 10-15 minutes' suspension, even in a well-designed harness. This effect is called suspension trauma.

The susceptibility of individuals to suspension trauma appears to vary greatly, and the fit and design of the harness no doubt has a major influence also. Unfortunately the commonly used fall-arrest harnesses which use an attachment point in the dorsal position, between the shoulder blades, are inherently unsuitable for hanging in suspended, because inevitably there will be pressure on the major arteries of the groin. This alone is a good reason for using a front attachment fall-arrest harness (with the attachment point at the chest), if the work situation suits it, as these harnesses are capable of taking the load primarily under the back of the legs, which is a much less sensitive area.

If a dorsal attachment point is used, it is preferable that there are no buckles or other hard elements in the groin area. It is now mandatory for harnesses manufactured to the Australian-New Zealand standard to incorporate an attachment point at the front of the harness (which may be two points that are connected together), to which a retrieval system operated by co-workers can be attached.

Suspension trauma is a risk to any worker who may suffer a fall and remain suspended. If a hazard assessment identifies such a risk, there must be a rescue plan which co-workers can put into use immediately in the event of a fall. This should include the availability of a retrieval system on the site.


Fall protection equipment requires careful maintenance. A record must be kept for each item showing its date of purchase and recording periodic inspections carried out at a specified interval. Typically, this could be done every six months. br /> Ropes, harnesses, and lanyards should be stored away from sunlight in a cool place. Metallic items should be stored in a dry place. All equipment should be kept as clean as possible.

A retirement guide-line must be available so that any deterioration or excessive use of the equipment can be compared with the guideline, and if permitted deterioration or usage levels are exceeded, the item must be retired, usually by destroying it. This link will take you to the website page on Equipment Inspection.

Harnesses and other webbing equipment should be checked for wear and damage to the webbing and stitching, distortion and corrosion of hardware, and correct function of buckles. Webbing equipment should not used for more than ten years, even if it is apparently in good condition.

Ropes should be checked for cuts and abrasion damage. The rope should have a uniform feel along its length. Ropes also should be retired after a maximum of ten years.

Karabiners, snap-hooks, and screw-links should be checked for correct function of the closure. If sprung latches are not closing properly, they should be cleaned and lubricated carefully, and retired if the problem cannot be resolved. Triple-lock karabiners are particularly prone to closure failure.

Self-retracting life-lines should be inspected according to the manufacturer's instructions, and returned to the supplier if maintenance is required.

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