Recommendations and Solutions 

• Have a good storm forecast system in place, get regular updates
• Don’t rig during the known storm season in your part of the world
• Derig the highline if any storm comes near your highline, don’t risk partial damage under the tapes which you can’t see
• We always recommend to derig and check properly if you are unsure.
• Detape lines and inspect on a regular basis, so burn marks can be found.
• We need to find alternative solutions to our current taping and technical solutions in our highlines (e.g. conducting elements along the line). For details and some ideas and recommendations check the discussion below

A Balanced Approach: Transparency Meets Responsibility

The ISA’s approach ensures transparency while prioritizing the safety and privacy of individuals. Reports are manually reviewed, anonymized where necessary, and checked through a “four-eye principle” process to minimize errors.

This effort is driven by a commitment to protect people—even when they may not protect themselves.

Will we make mistakes and be slow sometimes? Yes, but that’s part of the process. You are also welcome to help us speed up things in a responsible manner!

Why Publishing Accident Reports Is Complex

While the ISA is committed to providing access to critical safety information, publishing accident reports is far from straightforward. Here’s why:

1. Checking accuracy of reports

Not all reports are clear or complete. Differentiating between incidents and significant accidents is crucial. Reports sometimes contain conflicting accounts, missing details, or errors that must be clarified. Some incidents might generate multiple reports of the same event. Often additional investigation is needed to verify them and confirm their validity. Volunteers within the ISA will take the time to ensure that accurate information is shared

2. Respecting privacy of all involved parties

Images or videos accompanying reports often include graphic scenes and quite often show bystanders who did not consent to being publicly featured. Additionally, European law classifies medical data as critical personal data, necessitating anonymization and adherence to GDPR requirements. Responsibilities on data management need to be defined and data deletion needs to be institutionalized as well. We apply these strict principles on all data. In a smaller percentage of reports full anonymisation has to be applied. 

3. Respecting Legal Processes

Severe injuries and fatalities can lead to legal proceedings. Publishing reports on these cases prematurely could interfere with ongoing legal investigations or trials. Everyone deserves the presumption of innocence until proven otherwise. Different nations also have extremely varying laws regarding accident reporting, privacy, and liability. The ISA must respect these legal and sometimes cultural nuances.

New lifetime recommendations for highline webbing:

We created a more specific UHMWPE (=Dyneema/Spectra) webbing category from which our database does not (yet) allow to make precise recommendations for lifetime, due to a small amount of datapoints that fit the category. We hope to change this with a new long-term test series starting this summer.

The following chart describes the recommended maximum lifetimes (RLT) for webbings of different strengths and materials. These lifetimes are to be interpreted as “days exposed to the elements / days in use” and NOT as the literal age of the webbing (date from manufacture).

These numbers account for an average of 3000 J/m2 dose per day over the course of one year

Many equatorial and high altitude regions have much higher UV dosages than 3000 J/m2 average dose per day (averaged over the year). Also the dosages fluctuate massively during seasons (summer – winter), this needs to be taken into account by the user.

These numbers represent the recommended lifetimes for normal use. Intensive use (festivals, competitions, etc.) or harsh environments (strong UV, high winds, sand, salt water, etc.) can drastically reduce the lifetime of highline webbing.

It is strongly recommended that webbing owners document the number of days the webbing was used for, to have a good understanding of when to retire the webbing from highline use.

“No recommendation” indicates that there is not enough data to provide a general recommendation – it is up to the manufacturer to suggest a lifetime, and the end user to determine a webbing’s continued suitability.

Study supported by:

Some impressions from the past tests:

Thanks so much to the numerous people helping with preparing, sampling, testing and writing up this report!

Here you can see how this topic evolved over the years and will keep evolving once we gain new insights.

Installing the webbings at 3500 masl:

Lab testing of the webbings:

Presentation from the ISA Safey Event 2023:

Presentation from the ISA Safey Event 2022:

Presentation from the ISA Safey Event 2020:

Some impressions from the tests:

Thanks so much to the numerous people helping with preparing, sampling, testing and writing up this report! Special thanks to Rafael Thomele for hosting us at Käppeli, Switzerland.

The standard has allowed lots of festival organisers and professional riggers to better negotiate access and safety with insurance companies, landowners and officials from a local to a national level.

The ISA:21 Highline Systems Standard is a formal engineering definition and description of what a highline is and what the various components it consists of are.

On one hand this standard provides a framework for highliners as well as slackline manufacturers to understand what components are where and how they interact. On the other hand, it also provides a legal framework for highlines to be categorized as temporary installations and even permarigs with the prober maintenance checklists in place.

In addition to that, it also defines the forces that are acting upon the webbing, anchors and the highliner. In essence, it allows our partners, testing laboratories and technical engineers to communicate more effectively.

This standard further allows manufacturers to sell highline gear legally without being certified according to PPE standards. For this manufacturers further have to certify the individual components of the highline system.

Check out the list of highline certified products, more coming shortly:

Can’t find your highline gear on this list? Ask your manufacturer about certifying it!