Bridge climbers, Rope access, structural inspection

Using chain to wrap the top chord of the truss you're accessing would eliminate any problems regarding the size of the chord. The chain could be clipped with a biner attached to lanyard, etc... This would also allow you to provide your safety people with more reliable break strength figures than using soft gear to attach to members and risking abrasion/cuts. And of course, as you said, you could only clip the upper chord as a matter of routine. There's no way to safely use the truss webbing.

This would work well for small trusses that could be reached. The large ones? Maybe some kind of pole could be used to overcome the reach. I'm grabbing at straws. It could be constructed as part of lanyard system? A hook-over of some sort?

And yes the lanyards would be used in tandem, redundant, like a via feretta.

Chain would be a great anchor for them, but I don't see it as practical due to the amount they would need to carry, and that they would not be allowed to leave fixed pieces on the structure. For rope access, they need to be able to repeat the process on each structure of the type illustrated. For what they're doing, it would seem that short slings would be more practical, as even carrying enough slings to, say, toss a long one with a biner on the end over the top truss at various intervals would be excessive, let alone chain.

Too bad there's no simple device that would clamp onto a flat/square tube, similar to vice grips to make life easier, eh? Cam in reverse?

SPRAT was a solid reply. If you hold a cert, then you know. All situations should have been covered in your L3 training. I really hope you have L3 supervision.....just saying.....

FWIW I have been in Rope Access for a hot minute.

johnnyrig wrote: I don't see it as practical due to the amount they would need to carry, and that they would not be allowed to leave fixed pieces on the structure.

They would only need to carry two short pieces of chain, each long enough to wrap around the top chord. The procedure would be to start by wrapping both around the top chord, each clipped with its own lanyard to the harness. Then climber traverses the truss until he encounters an obstruction. Then he unclips one, reinstalls it on the other side of the obstruction, clips in to it; repeat process with second chain/lanyard. Continue traverse. Would require no belay and he could move independently in any direction. If he used a lanyard such as a purcell, he could adjust it manually to length without unclipping, depending on need.

I was thinking along pretty similar lines to what Doug had come up with. But a rigid system that sat on the top chord and rolled along with the inspector. You would have to move it every time you came to a cross member though, requiring two of these devices. and that could be rather difficult with the larger structures.

Thanks doug. makes more sense now.

Jacob, what if it was a hook something like this?

hook
It could be fabricated with 1/2 or 5/8 inch bar pretty cheap. Lower eyelet for a clip-in point. It would have to be long enough to reach the upper chord of the truss of course. And yeah, you'd need two. It could only fail if you fell upwards, right?

Daryl Allan wrote: Regarding Benlucky's suggestion, is there a requirement for you to inspect the truss from the inside or can it be done from outside the truss?

We have to be able to observe, visual or tactile, deficiencies in the structure or attached sign panels. The freedom to move around allows you to see a lot more. I've definitely scooted on my share of bridge trusses though.

Daryl Allan wrote: The more I think about this method though (leading), the more it seems that the additional gear is going to increase the risk of a fall. :/

I wonder that too. Our current system, while potentially unsafe in certain scenarios, is simple. No cluster F of excess slings, lanyards, ropes, anchors, etc. Fatigue from messing with all of this in August in Florida, I'm guessing, could increase the likelihood of fall.

johnnyrig wrote:Am I getting this correct? One guy walks the truss from the bucket truck, across, then back. Double lanyards, alternately connecting to each strut as the only anchor point, which if he falls he faces the possible sawing effect and maybe or maybe not dangling low enough for a possible truck strike? If the lanyard whips down the strut along with you, and you hit the bottom after an additional six foot fall, I would think that falls under the same scenario as falling on a daisy or sling from above an anchor. Bad juju. If you're crossing from one side to the other in a single direction and exiting the other side, I can see how adding a roped belay would inconvenience you from a time perspective, even if conducted in multi-pitch style. If you're crossing then returning, other than the inconvenience of carrying a number of slings, I don't follow how that would reduce efficiency substantially vs the gain in safety factor... And finally, since you're obviously not going to retrofit these trusses with catwalks or safety cables, would a kleimheist or similar friction hitch hold slings in position on the struts (even though they appear to be square/rectangular)? If so, that could eliminate the sliding/sawing effect and/or make a roped belay feasible. You said yourself, it's a matter of safety vs efficiency. Yes, there hasn't been a fall in 10 years, but how many accidents would it take to negate the gain in efficiency you get by sacrificing safety?

Yes, Johnny, you got it.

We typically boom up in the bucket, cross the truss, and boom down on the other side. This allows the other member(s) of the crew to inspect the foundation elements and take necessary measurements on the ground.

Any sort of belayed lead climbing would occupy another crew member's time for the duration of the truss inspection.

I like the friction hitch idea. I'll mull that over.

TylerPhillips wrote:SPRAT was a solid reply. If you hold a cert, then you know. All situations should have been covered in your L3 training. I really hope you have L3 supervision.....just saying..... FWIW I have been in Rope Access for a hot minute.

We've hired L3s for consultants in the past. The over complicated everything. They'd have so many high-line, anchors, re-belays strung out through these trusses. They don't understand the production side of what we do as inspectors.

Doug S wrote: They would only need to carry two short pieces of chain, each long enough to wrap around the top chord. The procedure would be to start by wrapping both around the top chord, each clipped with its own lanyard to the harness. Then climber traverses the truss until he encounters an obstruction. Then he unclips one, reinstalls it on the other side of the obstruction, clips in to it; repeat process with second chain/lanyard. Continue traverse. Would require no belay and he could move independently in any direction. If he used a lanyard such as a purcell, he could adjust it manually to length without unclipping, depending on need.

I think this is the best option, doesn't necessarily have to be chain either. The top chord is round so we'd be happy with a soft goods. My only reservation with this is any long slings or ropes add complication and you 1000% cannot drop it down in traffic.

We've used purcells in the past. Now our lanyards are actual dynamic climbing rope with a prusik attached for adjustment. The prusik would slip, or break, in the event of a fall providing more energy absorption. Basically this:

stolen from ropeguerrilla.org/

Doug S wrote:Jacob, what if it was a hook something like this? It could be fabricated with 1/2 or 5/8 inch bar pretty cheap. Lower eyelet for a clip-in point. It would have to be long enough to reach the upper chord of the truss of course. And yeah, you'd need two. It could only fail if you fell upwards, right?

That's a very creative solution. I like it actually. Homemade equipment probably wouldn't fly with OSHA or our safety committee. Wonder if independent testing could satisfy their requirements.

Reached the maximum allowed posts in 24hr. Thanks to everyone that has chimed in. Been great to bounce ideas off you guys rather than just my parents over the Easter weekend.

Evidently this product already exists and is called a shepherd's hook. A Google search produced some results including some controversy regarding their use in tower situations. The pole can get hung up causing the hook to disengage. Yeah, OSHA would require one that's manufactured and tested for that purpose. Maybe it's worth a look. I imagine working one of those big trusses is a PIA.

Shepherd Hook
Cool topic. I hope you come up with something.

This is not the type of question to ask on a climbing forum. Horizontal progression on a beam is standard, basic SPRAT/ IRATA stuff. You need to be asking your boss these questions. If he is not providing you with the training you need to accomplish your job safely, he needs to be replaced. Go above his head to the boss' boss if he is not training you properly. Ensuring your subordinates are properly trained is leadership 101 stuff. If you are certified, you should have learned this in your level 1 class. If not, your boss should probably send you off to get SPRAT or IRATA L1 certified. They will teach you the correct way to do this.

In any case, regardless of how you do it, you absolutely must be sure you do not drop anything off the tower or fall below the bottom of the tower. Working over people poses an extreme liability risk and exceptional risk to the people below. It's strongly preferred not to allow people to walk/ drive or otherwise migrate under you. If it's unavoidable, EVERYTHING you take up MUST be leashed, no matter how small. Drop something as small as a bolt into traffic and you could kill someone. If you are working with parts, you need to put a catch tarp under your work area to stop items from dropping into traffic, although if you're just inspecting stuff this is probably not an issue.

Do you use a rope access kit? (Sit harness with three cowtails)

You would sling the upper bar (or highest you can reach) Either with three steel slings or three nylon slings and keep with two connected at all times. If you want to be
100% sure to not have any part of you body enter the hazard zone then weight the slings and aid climb horizontally in a position that allows your feet to not
Drop below the area.

Option 2: run a two rope right line
Across the very top (via option 1) so
All parties can have a vertical access point (some engineers we inspect with can not climb well and a rescue would suck from there)

Option 3: Hire me!

Sprat & Irata both cover aid climbing (irata Lv1 & Sprat Lv 2) the only thing not
Covered would be climbing above the hazard
Zone.

And all the "anchor" options listed other than
Standard traditional "rope access" anchors
Would void any Insurance If you did get hit.

Don't jerry rig a anchor out of homedepot chain. Take a rope class and
Hire a company to assist you.

Do you want to die?
Do you want a coworker to die?
Do you want to be financially responsible for said
Accident?

Jason have you tried using beam wraps for fall protection?

Beam wrap
Built to girth hitch beams and such the webbing is industrial grade and endures much abuse.
Using a couple being wraps along with a full body harness and a tie back lanyard system like the picture below will allow you to move via ferrata style back and forth with the beam wraps.
Tie back lanyard
You face quite the interesting dilemma balancing safety and production with the task at hand.

I hear ya on the overcomplicated thing. A good L3 will listen to your needs/budget vs safety and come up with a good plan. PM me if you would like a bid from a solid and reputable rope access company. We have been doing bridge work for over 20 years.

I was in the industry for about 20 years.
I'd have to say, you sound rather new.
Live traffic!? if you drop anything, anything, and it hits something ,you are liable, if you hit someone you have committed a crime.
One way or another, you have to close the lanes below.
Via Ferrata gear is not rated or certified for this type of work.
A breakaway lanyard with lobster claws might fit around these steel crossarms.
I'd probably string a lifeline, and maybe a catchnet.
Whoever owns this structure must have some idea of the laws in this state.
Unless you're in a third world country; liability is a fact of life.
Mario Molina
Aerial Engineers
New C.C.
Charles Taylor Comm
Westower
Western States Tower
Radco Comm