Slackline Safety Lines and Leashes: When and How to Use Them

Slackline safety lines and leashes are backup systems used mainly in highlining and sometimes in lowlining to prevent a fall to the ground or to reduce the risk of injury. A slackline safety line is a separate rope or webbing rigged above the slackline, anchored independently, to which the slackliner is attached via a slackline safety leash. The leash is typically a dynamic climbing rope or sling that connects the slackliner's harness to the safety line via a carabiner or a pulley. In highlining, safety lines are mandatory; in lowlining, many slackliners choose to practice without a safety line (slackline without safety line) once they have mastered basic balance and falling safely, as it offers more freedom and is quicker to set up.

When Do You Need a Slackline Safety Line?

Safety lines are essential when the consequence of a fall is serious: highlining (slacklines rigged high above the ground), waterlining over deep water with hazards, or lowlining over rocky or uneven terrain. For lowlining (slacklines close to the ground, usually under 1 meter), a safety line is optional; many beginners start without one but with a spotter or crash pads. A general guideline: if the slackline is higher than about 1–1.5 meters or over dangerous ground, use a safety line and leash.

What Equipment Do You Need for a Safety Line Setup?

A complete slackline safety line system requires:

• Safety line (main rope or webbing): Dynamic climbing rope (10–11 mm) or static rope, or flat webbing. Dynamic rope absorbs shock; static is more stable but can transmit higher forces.
• Anchor points: Two independent anchors (trees, bolts, or ground anchors) for the safety line, separate from the slackline anchors.
• Backup systems: Redundancy in critical components (e.g., two carabiners, backup knots, or a second sling) to prevent failure if one part breaks.
• Slackline safety leash: A piece of dynamic rope or a commercial leash with a carabiner on each end, or a single carabiner and a knot. Length should be adjustable from about 1 to 2 meters.
• Climbing harness: Essential for attaching the leash; it distributes fall forces safely across the body.

How to Set Up a Safety Line for Lowlining

Even for lowlining, a safety line can be useful for beginners or for practicing new tricks. Follow these steps:

1. Rig the slackline as usual between two anchor points, keeping it low (about 50–70 cm above ground).
2. Choose two independent anchor points for the safety line, ideally directly above the slackline ends (e.g., higher branches or an overhead beam). Ensure they are strong enough to hold a fall.
3. Stretch the safety line (rope or webbing) between these anchors, tensioning it moderately. It should be about 1.5–2 meters above the slackline.
4. Check that the safety line does not touch the slackline when you stand on it (to avoid tangling).
5. Put on your harness and attach the leash to the safety line with a locking carabiner. Attach the other end to your harness belay loop.
6. Test the system by gently weighting the leash before stepping onto the slackline.

Slackline Safety Leash: Types and Use

The slackline safety leash connects your harness to the safety line. Common types:

• Commercial leashes: Often made of dynamic rope with sewn loops and a sewn-in elastic section to keep the leash from dragging. They offer a swivel to prevent twisting and are easy to clip in and out.
• Homemade leashes: A simple dynamic climbing sling or a piece of rope with a figure-eight knot on each end. You can adjust length by tying knots or using a daisy chain.

The leash should be long enough to allow free movement but short enough to prevent a long fall. For lowlining, a leash of 1.5–2 meters is typical. For highlining, leashes are often shorter (1–1.5 meters) to reduce fall factor. Always use locking carabiners to prevent accidental opening.

Safety Considerations and Backup Systems

When using a safety line, consider these points:

• Independent anchors: The safety line must not share the same anchor as the slackline. If the slackline anchor fails, the safety line should remain.
• Backup knots: If using webbing for the safety line, tie backup knots near the anchors to prevent slippage.
• Redundant connections: Use two carabiners opposite and opposed on critical connections, or a backup sling.
• Regular inspection: Check all gear for wear, especially after a fall. Replace any damaged items.
• Spotter: Even with a safety line, a spotter can help control the fall and untangle the leash.

Slackline Without a Safety Line: When It's Fine and How to Stay Safe

Many slackliners practice without a safety line when the line is low and the ground is clear. Slackline without safety line is the norm for tricklining, longlining at low heights, and casual park sessions. To stay safe without a leash:

• Keep the line at a height where a fall is easy to absorb: under 1 meter for most people.
• Clear the area of rocks, roots, and other hazards, or use crash pads.
• Learn to fall safely: bend your knees, avoid reaching for the line, and land on your feet or roll backwards.
• Have a spotter when learning new moves or walking the line for the first time.
• Be aware of the pendulum effect: if you fall sideways, you may swing; keep bystanders away.

Comparison: With vs. Without Safety Line

Aspect	With Safety Line and Leash	Without Safety Line
Typical use	Highlining, learning new tricks on lowline, dangerous terrain	Recreational lowlining on grass, tricklining, experienced slackliners
Equipment needed	Safety line, two extra anchors, leash, harness, locking carabiners	Slackline only, optional crash pads
Setup time	Extra 10–15 minutes	Minimal
Freedom of movement	Restricted by leash, but allows aerial tricks with less risk	Full freedom, but falls to ground
Safety level	High, prevents ground impact if set correctly	Depends on height and surface; injury possible
Skill level	Any, from beginner to pro	Usually intermediate and above

Tips for a Great Park Day with a Safety Line

If you plan to set up a safety line in a park, coordinate with your group:

• Check local regulations: some parks may not allow highlining or permanent anchors.
• Use tree-friendly anchors (wide webbing or padding) to protect bark.
• Have a designated person to manage the safety line and spot the slackliner.
• Bring extra gear: spare carabiners, slings, and a first aid kit.
• Pack a picnic that is easy to eat with one hand (sandwiches, fruit, water) so you don't have to take off your harness constantly.

With good planning, using a safety line can be a simple addition that makes your slackline session safer and more enjoyable for everyone.