Edelrid Ohm

Initial Review: Edelrid Ohm

How To Safely Climb With Someone Half Your Weight Using The Edelrid Ohm

When I climb with my girlfriend I’m always concerned. While I take extreme caution not to take violent sport climbing falls while she belaying me, I weight 1.6x what she does. In those occasions when I do whip I know the forces placed on her are extreme. As I fall, she is pulled upward off the ground, occasionally hurling her towards the wall. Not only does this raise her chances of injury but also increases the posibility of groundfall. We always have her using a mechanically assisted braking device (ie Petzl Grigri, Trango Vergo) but the concern that she may be unable to hold a lead fall at all remains. The Edelrid Ohm is a new solution addressing this problem.

Edelrid graciously sent me the first one in Canada prior to their North American release in early 2017 and my initial review has been very positive.

How The Edelrid Ohm Works

Research conducted by the German and Swiss Alpine clubs have concluded that to safely belay the climbers weight should not exceed 1.33x the belayers. This is a very common issue with couples who climb together.

Risk exists for both parties.  The belayer may be thrown violently towards the wall and potentially sucked up into the first bolt but if their natural reaction is to shield themselves from impact with their hands, suddenly the climber is at risk for a further fall.   An increase in fall distance can also lead to the climber decking if they pull the belayer too high off the ground or potentially colliding midair.

The Edelrid Ohm is an innovate solution aimed to solve this problem.  It is an assisted-braking resister installed on the first bolt in lieu of a conventional draw. The rope passes through normally as the climber continues upwards but in the event of a fall the device mechanically cams upwards and v-shaped groove add progressive resistance and arresting the upward pull on the belayer.

The unique angles and natural camming action means that the Edelrid Ohm does not abruptly arrest the fall, rather it progressively controls the speed at which ropes passes through, allowing for a dynamic catch.   This increase in friction makes it easier for the belayer to maintain control of the brake strand and prevents them from being hurled off the ground or towards the wall.

This added element of safety and control means you can now safely belay someone who weighs twice as much as you do.

Installing the Edelrid Ohm

The drawings on the device and in the technical notes are easy to read and understandable, making installation simple. The Ohm was easy to load but clipping it to the first bolt was not something I’d want to do if the first moves were challenging.  Clipping in a rope was akin to one-hand Grigri installation and, while not difficult, was not something I’d want to fumble with if there was significant fall potential. and install on the first bolt.  We experimented clipped the rope through the device and then attached it to climbers belay loop until the first bolt and this worked well.  You could also clip a regular draw to the first bolt before adding the Ohm and retrieving your draw.
We attempted to stickclip in a few times and were successful but the added weight made aiming more of a challenge.

Edelrid Ohm
The images on the Ohm are easy to read and understandable.
Climbing with the Ohm

There was a negligible amount of friction added to the leader however it necessitated the climber to pull rope in a controlled manner to avoid engaging the device. High reaching clips had a propensity to briefly snag the rope before disengaging and serving as a gentle reminder to slow down.  I’ve seen a few climbing partners become quite agitated by this hindrance but I found it rather inconsequential.  If you’re regularly clipping above head height, this will require a slight change in your technique.

While Edelrid claims the device will only engage in the event of a fall, we noticed quick movements of the rope could snag often. While there was very little , if any, increased drag during the course of normal climbing but I was able to make the Ohm engage by quickly standing during a top out.

There was no added friction when the climber called for a take and the Ohm didn’t engage at all when pulling in rope.

Catching Falls Is Where the Edelrid Ohm Shines

As a climber, falling felt fine but was definitely a stiffer catch.  The Ohm allows for almost two feet of rope out as it cams upwards, allowing for a soft catch. As always, the more rope out, the softer the catch as more dynamics are in system so falling on the Ohm from the third bolt or the sixth did make a difference.

As a small belayer, catching falls is where the Edelrid Ohm stood out.  During our testing the greatest weight differential we used was a 215lb male falling 3m with a 115lb female belayer.  She barely left the ground. All testers commented that catching falls with the Ohm was soft and comfortable.

Most of the time device was easy to unlock after a fall if the leader was able to regain the rock and began to climb again. If the climber came to rest free-hanging below an overhand it took an occasional whip of the rope to get it smoothly lowering again.  Boinking was nearly impossible.


Lowering a climber was an area where the Edelrid Ohm fell short for me. On numerous occasions the climber would weight the ropes and this would be enough to engage the resisted braking mechanism.  On one such occasion we had to whip the rope fairly aggressively and had we not had a backup belayer in place it would have dropped the climber quickly and unexpectedly. I suspect this was in part due to the overhanging nature of the climb.

Multipitch Functionality

As the device is relatively new, I could not find any literature exploring the functionality in a multipitch setting. On challenging routes with bolted stations the Ohm has the potential to reduce the impact on the belayer in a dangerous Factor 2 Fall scenario.  However, it isn’t light and 330g is a lot of weight for a piece of specialty kit addressing a potential scenario that could easily be mitigated by employing the Fixed Point Belay.

Edelrid Ohm

Price $156 CAN
Weight 360g
Rope Diameter 8.6-11mm
Initial Conclusions of the Edelrid Ohm

Overall I’ve been very impressed with the elegant simplicity of the Edelrid Ohm.  It certainly delivers as promised and has expanded the range of suitable climbing options available to my girlfriend and I.  Like anything, it does have it’s limitations. At 330g it isn’t light and at a retail price of $156 CAD it isn’t cheap.  It should also be noted that the device is only intended for belayers who weigh more than 40kg, so any babysitters thinking of taking a small child to the crag and yarding on your project, please reconsider.

Its usage is very niche and nearly all the benefits offered can, in some capacity, be mitigated through technique improvement.  But for those who really need it, it is simply unbeatable.  The inconveniences of tricky lowering and slow leading are easily eclipsed by the quality of life enhancement for the small belayers.

The Edelrid Ohm will have a permanent place on my rack when heading out for easy cragging days with my girlfriend. If you’re in the Bow Valley they are available at Vertical Addiction.  Has anyone else had a chance to test out the Ohm?  Let me know what your thoughts were in the comments below.

Note:  While Edelrid sent me one of these to test, it in no way affects my views on the device.


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