Frequently Asked Questions

The two most common Connecting Devices are Energy Absorbing Lanyards (EAL’s) and Self-Retracting Lanyards (SRL’s).  As with Full Body Harnesses, choosing the correct connecting device is critical to the potential outcome, and requires careful consideration of all of the factors. 

One of the most disturbing trends in Fall Protection today is the practice of issuing a blanket mandate that all work­ers on a job-site be equipped with a Personal SRL – mandates such as these do not take into account the advan­tages and disadvantages of specific connecting devices, nor do they fully consider the myriad fall hazards that may exist and the fact that each of these hazards may have unique characteristics that cannot be managed by a blanket mandate.

First, it is important to understand that both EAL’s and SRL’s are intended to function as connecting devices for fall arrest purposes and that each of these devices contains a mechanism for limiting the forces associated with fall arrest.  With that said, it is of utmost importance to understand that these two types of devices have different capa­bilities and limitations and that they are absolutely not interchangeable.

EAL’s come in many configurations, and have their own very specific set of requirements, both within the context of OSHA Regulations and ANSI Standards.  As with most fall arrest products, the ANSI Standards go beyond the OSHA regulations in terms of creating testing procedures and performance requirements, and at the most basic level and EAL is expected to:

• Have a minimum static strength of 5,000 lbs
• Must limit the arrest forces associated with either a six or a twelve foot free-fall.
• Must arrest a fall with a maximum deceleration distance of 48” – 60” (depending on free-fall distance)
• Must be subjected to environmental conditioning tests
• Must meet specific requirements related to dual-leg configurations, tie-back configurations, etc.

SRL’s also come in many different types and configurations.  With that said, neither the OSHA regulations nor the ANSI standards have fully recognized many of these, and the requirements for these devices are not as stringent, nor are they as specific as the requirements for EAL’s.  In fact, the basic assumption of both the regulations and the standard is that these devices are generally always mounted overhead so as to limit the free-fall distance to no more than two feet.  The basic requirements for an SRL are as follows:

• Must have a minimum static strength of 3,000 lbs.
• Must limit the arrest forces associated with a free-fall of zero to two feet.
• Must arrest a fall in less than 54”
• Must be subjected to environmental conditioning tests

If you examine the basic requirements as outlined above, there are a few things that are a bit disconcerting.  First and foremost, SRL’s are not expected to be as strong as lanyards – and generally speaking, they are going to be weaker by a factor of 20 – 40%.  Furthermore, there is not standard or regulatory requirement for these devices to be put through testing with any significant free-fall imparted to the test mass, nor are application-specific variants required to go through any testing to evaluate whether they are fit for purpose.

In reality, SRL’s are generally superior to EAL’s if, and only if, they are tied off or mounted to an anchorage that is overhead and/or directly adjacent to the user’s back D-ring in a manner such that free-fall is limited to an absolute maximum of two feet.  There may be a very few specific exceptions to this rule – but it will be necessary to engage in very specific conversation with your manufacturer of choice in order to make that determination.  If you are to be subjected to a free-fall greater than two feet, in 99 out of 100 cases, you will be better off utilizing an application-ap­propriate EAL.

There are several FAQ’s in this series related to SRL’s – please take the time to read each of them, as you will find useful information that will provide a deeper understanding in terms of the advantages and disadvantages of these devices.  An important take-away is this:  SRL’s are among the most misused and misunderstood pieces of equip­ment in the fall protection arsenal.

This is a question that very few people can answer definitively and accurately.  There are a lot of misconceptions about SRL’s. Some of these have been exacerbated by new developments in the manufacturing sector and by newer requirements in the ANSI Z359 standards over the last five years.

Let’s begin by discussing what a traditional SRL is. Self-retracting lifelines are devices that contain a reel with an integral line tied to a heavy-duty clock spring. These devices have traditionally been mounted to overhead anchorages above the walking-work surface. When tied-off to an SRL of this description, the worker will have the ability to access a reasonably-sized working area. They have the additional ability to ascend or descend, with the SRL line either paying out or automatically retracting to eliminate slack. In the event of a fall, the reel will lock and begin the fall arrest sequence.

This was the landscape for SRL’s for many decades. In the early 2000’s, the first “compact” or “personal” SRL’s were introduced. These units were miniaturized and were offered as an alternative to energy-absorbing lanyards (EAL’s). Many manufacturers began prescribing them for “wear” on the back D-ring of a full body harness in lieu of the traditional EAL. Some of these were described as “fall limiters.” Many manufacturers claimed that they were superior to EAL’s because they reduced the tripping hazards associated with a fixed length lanyard hanging off of a user’s harness. They could also arrest a fall in a shorter distance since they didn’t require a free-fall distance equivalent to the length of the traditional 6 foot EAL.

The problem with this philosophy is that there were no testing requirements that created an accurate comparison of the capabilities of these “fall limiters” vs. the traditional EAL’s. As these early models were introduced, it wasn’t anticipated that they would be used to make connections to anchorages that were not always going to be overhead. As a result, these units were subjected to free-fall distances that weren’t anticipated by the testing protocols established in the OSHA regulations and the ANSI standards. The result has been a mixed bag of performance results. Many users have employed these devices in a potentially dangerous manner.

Additionally, the ANSI Z359.14 standard for SRL’s was published in 2012. This document took the original requirements of the earlier Z359.1 standard and expanded upon them. As a result of the introduction of personal SRL’s and the Z359.14 standard, we now have different types and classifications of products. Not everyone has a clear picture of what these types and classes are, what they are capable of, and what the appropriate uses and limitations are. Let’s examine these, and then we will break down how they work.

First, based on the language of Z359.14, we have three types of devices. A fourth type is being defined and is currently in the process of being drafted for a new edition. Each type is lumped together under the new name  “self-retracting devices” (SRD’s) which are defined as:

“A device that contains a drum-wound line that automatically locks at the onset of a fall to arrest the user, but that pays out from and automatically retracts onto the drum during normal movement of the person to whom the line is attached.  After the onset of a fall, the device automatically locks the drum and arrests the fall.  Self-Retracting Devices include Self-Retracting Lanyards (SRL’s), Self-Retracting Lanyards with integral rescue capability (SRL-R’s) and Self-Retracting Lanyards with leading edge capability, and hybrid combinations of these.”

Let’s briefly examine each of these, as well as the SRL’s of the personal type:

SRL’s: Self-retracting lanyards are intended to be mounted to a fixed anchorage, horizontal lifeline, or rail system or trolley. They’re generally mounted overhead, and they can be rigged to limit free-fall to a maximum of two feet. These devices provide a degree of lateral and vertical movement for the user.

SRL-R’s: This type consists of a self-retracting lanyard with an integral rescue capability. This capability uses an integral retrieval winch, which will allow a fallen or injured worker to be raised or lowered. These devices are most commonly used in confined space applications. They may be used interchangeably with SRL’s, provided that the rescuer has access to the rescue mechanism.

SRL-LE:  Self-retracting lanyards for leading edge exposures are required to have a supplemental energy absorber at the point of attachment to the user’s FBH back D-ring. These units are designed to protect steel erectors who may be exposed to leading edge falls. They often feature a larger diameter wire rope constituent line to resist cutting and abrasion. These devices should be used as a last resort, as the application has a high degree of risk. Also, the qualification testing required by the ANSI Z359.14 standard is not comprehensive. It doesn’t anticipate hazards that may be damaging to the SRL line, such as unbeveled concrete, metal decking and joints, or gaps between beams and columns.

SRL-P:  Personal or “compact” SRL’s are designed to be worn and utilized in lieu of energy-absorbing lanyards. These devices are ideal for attaching to anchorages that are overhead or directly adjacent to the back D-ring of the user’s full body harness. Not all units are tested in extremes of free-fall. The increased dynamic loads resulting from reduced anchorage height can produce forces that may exceed the capacity of the energy-absorbing element of the device. This may damage the structural integrity of the device if the energy-absorbing element is overloaded.

Having described and defined the basic types, there are also two classes that are specified in the ANSI Z359.14 standard that apply to the SRL, SRL-R and the SRL-P:

• Class A devices, when subjected to dynamic performance testing, should have an arrest distance not exceeding 24 inches, a maximum arrest force of 1,800 pounds, and an average arrest force of 1,350 pounds.

• Class B devices, when subjected to dynamic performance testing, should have an arrest distance not exceeding 54 inches, a maximum arrest force of 1,800 pounds, and an average arrest force of 900 pounds.

Note: These performance thresholds only hold true in actual practice if the SRD’s are mounted overhead. In the event of a free-fall, the performance characteristics will change, particularly with respect to the SRL-P or Personal Device.

Now, we can discuss the functional elements that make an SRD work. There are two principle elements that are critical to fall arrest: the locking mechanism and the energy-absorbing element.

There are three ways to create a locking engagement of the drum in a SRD:

Centrifugal locking mechanisms are the most common. These consist of one or more pawls, or an articulating lever or claw. They’re activated by the centrifugal motion of the drum as the line is extracted during the course of the fall. As the pawl swings outwardly, it engages the teeth of a gear, ratchet ring, or sperrad in order to create the locking engagement. The downside of this type of mechanism is that it can be susceptible to fouling. This caused by corrosion or invasive contaminants, including dirt, grease, or oil. If fouling occurs, the mechanism may fail to engage.

Inertial Locking Mechanisms are similar to the seat-belt assemblies in automobiles and function on the basis of acceleration. The acceleration of the spinning drum after the initiation of a fall spins an internal shaft. It puts pressure on a lever assembly that will force a locking engagement to take place. These mechanisms aren’t popular as they’re overly complicated. They also don’t work well in sliding falls or engulfment scenarios, such as in grain silos.

Mechanically-Activated Locking Mechanisms are similar to centrifugal locking mechanisms in that they will also feature locking pawls (generally two or more). In this case, however, the pawls are not entirely dependent on centrifugal force. Instead, they’re driven into engagement by a rotating cam. The advantage of this type of mechanism is that it is not susceptible to failures caused by corrosion or invasive contamination. They are typically more expensive to manufacture, but are the most reliable.

Once the locking engagement has taken place, the SRD needs to dissipate the forces associated with a fall arrest to protect both the worker and the integrity of the anchorage. This is where the energy-absorbing element comes into play.  

There are three basic methods used in SRD’s to absorb energy:

Rotary Brake Method: This is the traditional method, particularly for versions utilizing wire rope as the constituent line. The rotary brake is an assembly consisting of a pressure plate and an abrasive brake disc. The disc is located on one side of the drum, and is held in place by a nut and belleville washer on the axis of the main-shaft or axle. When the locking engagement takes place, the drum is allowed to continue spinning under the pressure of the brake, bringing the falling mass of the user to a stop. This is the most efficient and effective method of absorbing energy, as this brake assembly can generally be tuned to achieve desirable results. Additionally, if the unit has a reserve line (excess line that can’t be pulled out of the unit under normal circumstances) the energy capacity can be virtually unlimited, dependent on the length of the reserve line.

Compression-Elastic Method: This is also a traditional method, but it’s only relied upon in units that use polyester or nylon webbing for the constituent line. In this method, the natural elasticity of the webbing itself, and the tightening or cinching of the webbing around the drum following the locking engagement, is sufficient to absorb the energy associated for a fall. This is provided that the unit is mounted overhead. The downside of this method is that if the unit is not mounted overhead, any significant free-fall can result in a serious force-spike. The force-spike can result in an MAF greater than 1,800 pounds, or in some cases, greater than 3,000 pounds.  Additionally, if the webbing is significantly worn or degraded, its ability to manage forces may be considerably diminished.

Tear-Tape Energy Absorber:  In the case of some smaller devices, particularly SRL-P’s, a tear-tape energy absorber is utilized. This is not unlike the type you would typically see on an energy absorbing lanyard. More often than not, this element will be located adjacent to the anchorage-end connector. Once the device has locked up, the tear-tape takes over and expands as it would on a lanyard. This brings the falling user to a stop with a maximum arrest force of less than 1,800 pounds. This method is effective. However, in some cases, a shorter length of tear-tape is used - as very little is required to pass the ANSI Z359.14 testing. If any significant free-fall may occur, then additional energy absorber capacity may be required.

As we have illustrated here, how SRL’s work is a somewhat loaded question. There are a lot of issues to consider, and these devices are not necessarily as straight-forward as they may seem.  It is important to work closely with your manufacturer of choice or with a competent distributor to make sure that you are selecting a product that is appropriate for your application. Self-retracting devices are a great solution, but they are not always the best choice. Do your homework before making decisions about how these devices are to be employed by your organization.

The ANSI/ASSE Z359.0-2012 standard says, “swing fall is a pendulum-like motion that occurs during and/or after a vertical fall. A swing fall results when an authorized person begins a fall from a position that is located horizontally away from a fixed anchorage.”

Swing falls are typically associated with the use of a self-retracting lifeline, primarily because an SRL can be installed at a height greater than that of a shock absorbing lanyard. If cable is paid out of the device as a result of the user moving away from the device horizontally, a fall (and the subsequent locking of the SRL) will cause the user to ‘swing’ like a pendulum back towards center.

These are two terms are often used interchangeably in the Fall Protection business. In reality, self-retracting lanyard is the preferred term, based on the types and classes of self-retracting devices that were further defined in the ANSI/ASSE Z359.14 standard back in 2012.

This is dependent on the manufacturer. There are some manufacturers that do not require recertification or periodic factory authorized service. Those manufacturers that do typically go with a period of every one to two years.  

The ANSI/ASSE Z359.14 standard published in 2012 included a specific schedule as a normative part of the standard. In 2014, the schedule was revised to be optional due to complaints registered by a small number of manufacturers and end-users.

The current, recommended guidance from the Z359.14 standard is as follows:

Keep in mind that the environment that the device is used in, and the behaviors of the users themselves will ultimately dictate the frequency of recertification. Be sure to follow the guidance for pre-use.

Not necessarily. There are several factors that may make one SRL better than another. If you want to get the best SRL, look for these things:

Mechanically Activated Locking Mechanism: This type of locking mechanism is the least likely to be susceptible to failure resulting from corrosion or invasive contamination. Contamination can occur due to dirt, oil, grease, paint or any other substance drawn into the device by the constituent line as it pays-out and retracts.

Energy Capacity or Free-Fall Rating: The capability of the device to deal with severe dynamic loads while limiting forces is critical. Many manufacturers simply “test to the standard,” which does not require imparting free-fall to the test mass in an effort to quantitatively determine how the device performs. This is particularly crucial when we are looking at personal SRL’ s. Seek out devices that have been tested beyond the scope of the ANSI Z359.14 standard.

Ultimate Strength: Would it disturb you to know that SRL’ s are the only product class that is not required to provide at least a 2:1 safety factor in static testing under the ANSI Z359 standards? The minimum strength requirement is only 3,000 lbs., while the maximum arrest force is allowed to be as high as 1,800 lbs. Many SRL’ s are capable of sustaining a higher static load. Seek these units out, as the residual factor of safety is higher.

In terms of construction, many plastic cases are merely “shells,” and the SRL may feature an aluminum or steel frame. The shell, in this case, is not load-bearing, but merely exists to protect the internal components from the elements.     

In some cases, the plastic housing may be semi-structural. This means that it is reinforced with steel or aluminum elements which are designed to carry the fall arrest loads. Generally speaking, devices with metallic frames and/or reinforcements are going to be just as capable as those with metallic housings.

In some plastic units, the plastic housing is load-bearing. While these may meet the requirements of the ANSI/ASSE Z359.14 standard in new condition, it is important to note that a damaged case may be a significant hazard.

Engineered plastics have come a long way. However, it’s important that you “pop the hood” on an SRL before you make a purchasing decision so that you know what you are getting. The material of the housing is not as important as what the housing may be concealing from your view prior to making a buying decision.

There are several differences, but the most noticeable difference is simply the size, or the working length. Most compact or personal SRL’ s are offered in working-lengths of 6 feet, up to a maximum of 10 or 12 feet. Anything longer than that starts to become a little unwieldy. Since these devices are generally used interchangeably with energy-absorbing lanyards, there is an expectation that they be small and reasonably lightweight.

Another difference is that the constituent line in a personal SRL is typically going to be webbing. Larger, full-size SRL’ s are going to use wire rope. The reason for this is also to control the size and the weight. Wire rope weighs more than webbing, and also requires a wider drum diameter in order to be effectively wound.

Finally, most full-size SRL’ s utilize an internal rotary brake to manage energy absorption. Due to the constraints on the size and weight of the personal devices, this is typically not practical. External tear-tape energy absorbers are generally used on smaller devices.

This depends entirely on the application. It is pretty rare to see personal SRL’ s mounted to overhead anchorages in the manner of a larger traditional unit. A common exception is when these devices are mounted to order-picking lift-trucks. Since the walking-working surface is so small and since there is an integrated anchorage overhead, this is a practical solution in that application. Outside of this scenario, it is a pretty rare practice.

In any event, always be sure to mount and/or wear these devices in accordance with the manufacturer's instructions. Your manufacturer of choice and your competent and qualified persons will always be your best resource for guidance on what is appropriate for your equipment.

This would be the best option in a scenario where your anchorages are routinely located at or above the level of the back D-ring of a user's FBH. In these situations, the arrest distances will be limited and your clearance requirements will be reduced. If you do not have these types of anchorage elevations, you need to reevaluate your desire to use personal SRL’ s. Many may not perform as well as you think. You may find yourself with inadequate clearance, or with a device that may not be capable of dealing with the force inputs that will result from a fall arrest.

The prevailing consensus is that personal SRL’ s are better or more effective than energy-absorbing lanyards. This is not universally true, and in many cases it’s entirely false.    Please be sure to consult with your manufacturer of choice or a competent distributor for specific details and assistance.

Many, if not most, compact or personal SRL’ s feature a separate or external tear-tape energy absorber. The simple reason for this is that these devices are expected to be small, lightweight, and economical. As a result, incorporating an internal rotary brake is a significant challenge, particularly when you factor in the need for a reserve line.

The most effective way to give the customer what they want, along with the energy-absorbing capability they need, is to use an energy absorber of this type.