The Essential Guide to ANSI Class 2 SRLs
Posted by info@customdigitalsolutions.co BigCommerce on Mar 18th 2025
ANSI Class 2 SRLs: An Essential Guide
ANSI updated its Z359 standard with new classifications and safety testing for self-retracting lifelines (SRLs). The new Class 2 SRL received special focus in the new standard. Discover why.
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One thousand—that’s the estimated number of the US construction industry’s work-related deaths per year. Almost 400 of these workers died from slips, trips, and falls in 2021 alone.1 That was also the same year a new ANSI standard arrived aiming to enhance worker safety and put a dent in fall-related deaths and injuries.
You may have heard about these guidelines: ANSI Z359.14-2021 became effective on August 1, 2023, two years after publication. The American National Standards Institute (ANSI) and the American Society of Safety Professionals (ASSP) enacted the guidelines to simplify classifications and increase safety on Self-Retracting Lifelines (SRLs).
Of the two new classes, the Class 2 SRL has received the greater attention from regulators and users. That attention, in turn, has sparked questions like:
- What is a Class 2 SRL?
- What is an SRL-P?
- Is a Class 2 SRL better than a Class 1?
- Where do I use a Class 2 SRL?
Let’s break down the essentials you need to know about Class 2 SRLs.
A Primer on ANSI Z359 Types and Classes
ANSI first set guidelines on fall protection equipment in 1992 with the Z359.1 Fall Protection Code. Two decades later, ANSI updated its standard with guidelines for Self-Retracting Devices (SRDs), including SRLs, with Z359.14. The 2012 guidelines divided SRDs into Class A or B based on overhead anchorage performance. A revision in 2014 defined that a steel edge sharpness in leading edge testing be 0.005 inch.
The latest standard, Z359.14-2021, classifies SRDs into three types:
- Self-Retracting Lifeline (SRL)
- Self-Retracting Lifeline – Personal (SRL-P)
- Self-Retracting Lifeline - Rescue (SRL-R)
ANSI defines an SRL as a “mechanical fall arrester, featuring a locking mechanism and energy management system to arrest the fall and limit the forces imparted to the user.”2 An SRL-P is meant for individual use and mounted onto a full body harness. An SRL-R is a mechanical fall arrester with the added function of rescue and retrieval post-fall arrest, by raising or lowering a fall-arrested user to safety.
| Class A | Class B | Class 1 and 2 | |
|---|---|---|---|
| Max Arrest Force | 1,800 lbs. | 1,800 lbs. | 1,800 lbs. |
| Avg. Arrest Force | 1,350 lbs.* | 900 lbs.* | 1,350 lbs.* |
| Max Arrest Distance | 24 in. | 54 in. | 42 in. |
| *The Average Arrest Force limit increases during hot, cold, and wet conditioned tests. | |||
The latest standard categorizes SRDs into Class 1 or 2 versus the earlier Class A and B. Above shows key performance requirements between them.
What is a Class 2 SRL?
An ANSI Class 2 SRL has two key criteria.
First, a Class 2 SRL anchors at, above, or up to 5 feet below a dorsal D-ring tie-off. This differs from a Class 1 SRL which anchors at or above a dorsal D-ring only.
Second, a Class 2 SRL has a retractable lifeline tested and rated for use within leading edge environments. By contrast, a Class 1 SRL’s lifeline is not rated for such use. Why the leading-edge requirement? ANSI concluded that a user tying off below D-ring has a high likelihood of his or her potential fall seeing an edge hazard.
To address this possibility, a Class 2 SRL has its lifeline tested in drop tests along a thin steel edge 0.005 in. (0.13 mm) thick. To put that sharpness into perspective, a razor blade’s maximum thickness is 0.0105 in. (0.27 mm).3
Is a Class 2 SRL Better Than a Class 1 SRL?
It’s best not to think of which class is better. Because it supports below-D-ring anchorage and is rated for use near leading edges, a Class 2 SRL gives users a greater range of potential use on a worksite.
When and Where to Use an ANSI Class 2 SRL
Best practice assumes a worksite operates in compliance with ANSI’s latest standards. Under ANSI Z359, a Class 2 SRL is required whenever work conditions increase fall energy or create leading-edge exposure.
Any ANSI Z359-compliant worksite therefore requires a Class 2 SRL:
-
When a user ties off below the D-ring, including waist-level or structure-mounted anchorage
-
When a user is exposed to a leading edge, such as steel members or concrete edges
In many elevated work environments, these two factors occur together. SRL-Ps are often used to improve mobility and reduce bulk. When anchored below the dorsal D-ring, however, free-fall distance and arrest forces increase. If sharp or abrasive edges are present, the performance demands on the lifeline increase as well.
These conditions are common in sectors such as utilities, industrial maintenance, and energy production, where workers may also operate near energized equipment. In these higher-risk settings, selecting equipment that is tested for both below-D-ring anchorage and leading-edge contact is critical.
A Class 2 SRL is designed for these applications. It supports anchorage at, above, or up to five feet below the D-ring and includes lifeline testing for leading-edge exposure. It is built to manage the higher arrest forces that can result from these configurations.
To reiterate, best practice assumes ANSI compliance. Where elevated fall energy or edge exposure exists, a Class 2 SRL is the appropriate and defensible choice.
How to Identify a Class 2 SRL
The new ANSI standard requires an SRL to have two identifiers.
First, every Class 2 SRL must have a label that appears exactly as above. The label will measure 1 inch for SRLs and a ½-inch for SRL-Ps.
Second, every Class 2 SRL must have a chart or diagram that shows the minimum required fall clearance. See FallTech’s version above for reference.
Can You “Grandfather” or Convert an Old SRL to Class 2?
You cannot grandfather a Class A or B SRL to a Class 1 or 2 standard. An SRL only complies with the standard on its product label. A 2014 Class B SRL-LE, for example, does not comply with ANSI's 2021 Class 2 standard. The testing criteria have changed, and safety factors have increased.
Contact your manufacturer to find out if it offers an upgrade process for your SRL like FallTech.
In summary, a Class 2 SRL:
- Anchors at, above, or up to 5 feet below a dorsal D-ring.
- Is rated for use in leading edge environments.
- Must have a “Class 2” label and fall-clearance diagram.
For references, browse FallTech’s list of industry-leading Class 2 SRLs. For all things related to fall protection, always stay connected with FallTech!
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