Questionable Rigging

stgtech91

Member
Hey all,
I am being asked to hang some lights on truss that was hung in a manner which seemed questionable to me after having basic rigging training. It has been made clear that refusing to do so will result in the loss of my job. I spoke with several riggers and brought one onsite and they all seem unanimous in the opinion that it is not currently safe. However, I have not yet found any code or regulation that specifically prohibits- nor supports- it being done this way.

Could someone point in the right direction? Thank you in advance!
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Your picture link is broken, so no help there.

Rigging standards for the industry are all here: http://tsp.plasa.org/tsp/documents/published_docs.php

You might find what you need to back yourself up there, you might not. Get that picture working and we can point you in the right direction. Upload it to photobucket then share it here. That tends to work better.
 
"negligence" and similar concepts are referred to in most laws, codes, standards and company policies. Doing something you know is wrong makes you responsible for the consequences.

The issue is really that you think it's wrong and the boss says it's not. I suspect the best course is to come up with an improvement/addition that isn't too expensive/time consuming that the bosses will let you put into place.
 
The strut is not actually the problem there. The problem is everything else. All easily fixable though.

I am assuming the following here... and you need to confirm all of this before you throw it all under the bus...

-That is proof coil 30 chain
-The eye bolts are not forged
-The eye bolts are held on without locking nuts
-The chain is attached to the eye bolt with a quick link or the eye bolt was installed on the chain by opening the eye bolt

If that is the case, you can go to our rigging standards to kill all of this
-Grade 30 chain can only be used in a basket configuration with two points of contact
-Only rated and forged eye bolts can be used for overhead lifting
-All hardware must be grade 5 and locking

How are the chains attached to the steel?

All in all though, two batten clamps and a bit of steel and beam clamps will fix this up rather quickly... all for a few hundred bucks.
 
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The strut is not actually the problem there. The problem is everything else. All easily fixable though.

I am assuming the following here... and you need to confirm all of this before you throw it all under the bus...

-That is grade 30 chain
I was told it was high test chain which to my understanding is grade 43 and still unsuitable for overhead lifting

-The eye bolts are not forged
This is correct- I am not sure if they are bent or welded shut

-The eye bolts are held on without locking nuts
I was told lock washers were used instead of locking nuts

-The chain is attached to the eye bolt with a quick link or the eye bolt was installed on the chain by opening the eye bolt
I am not sure how it was attached

If that is the case, you can go to our rigging standards to kill all of this
-Grade 30 chain can only be used in a basket configuration with two points of contact
-Only rated and forged eye bolts can be used for overhead lifting
-All hardware must be grade 5 and locking
Where are these standards actually published? I looked through the PLASA docs previously but everything seemed specific to motorized or counterweight rigging.


How are the chains attached to the steel?
The chains are attached to the beam by going between the center of the two pieces of angle steel beam with an inverted eye bolt.

All in all though, two batten clamps and a bit of steel and beam clamps will fix this up rather quickly... all for a few hundred bucks.
That is essentially the setup I was proposing- it was refused due to me not having code to back up my claim that the current implementation is not safe
 
Is this a staticky suspended system?
 
The chains are attached to the beam by going between the center of the two pieces of angle steel beam with an inverted eye bolt.

Yuck. Truly, that is your biggest issue. Everything is hanging on an 1/8" of a nut. Probably a washer as well for "good measure".

I have a feeling your boss is the one who rigged it and that is why you are getting push back. Let the chain thing go. You get into the "overhead lifting vs dead hanging" argument. In reality, the truss will blow apart way before the chain. Your attachment points are the real issue. You need to get those non-forged eye bolts out of the air. Also, that load is being supported by a washer that already looks like it is puckering. I can't find the specific code that says non-forged eye bolts should not be used. I'm sure ANSI has it and @egilson1 will be able to point us in that direction. If the eye bolts are not stamped they can't be used anyway.

Get a real beam clamp and a pipe clamp and a few shackles. You are looking at 15 bucks a point to get it right. It is a no brainier.
 
PURELY a knee jerk rank amateur reaction but the image kind of reminds me of the structural failure that caused Hyatt Skywalk collapse July 17, 1981. Way different components and all, but I have a wide awake nightmare where the nut and washer pull through the unistrut (or whatever that supporting piece is)
 
I can't find the specific code that says non-forged eye bolts should not be used.

The forged hardware requirement is in ANSI E1.4 3.18.3.3. You'll find the requirement for grade 80 overhead lifting rated chain in the appendix for 3.18.3.3 too. The deal there is, like Kyle said, you can only use grade 30 chain with a double load path as in a typical counterweight trim chain situation. Otherwise chain needs to be rated for lifting.

E1.4 is named as a manual counterweight standard, so I guess if someone wanted to continue being a stick in the mud they could say "this is dead hung so show me that standard" but by that point it is probably time to walk away from the job. When I've seen an inspector cite malleable hardware in dead-hangs during rigging inspections they have cited E1.4.
 
The forged hardware requirement is in ANSI E1.4 3.18.3.3. You'll find the requirement for grade 80 overhead lifting rated chain in the appendix for 3.18.3.3 too. The deal there is, like Kyle said, you can only use grade 30 chain with a double load path as in a typical counterweight trim chain situation. Otherwise chain needs to be rated for lifting.

E1.4 is named as a manual counterweight standard, so I guess if someone wanted to continue being a stick in the mud they could say "this is dead hung so show me that standard" but by that point it is probably time to walk away from the job. When I've seen an inspector cite malleable hardware in dead-hangs during rigging inspections they have cited E1.4.

Please read 1.4 again. I dont believe it requires Grade 80 nor does it give blanket approval to grade 30 under any circumstance. It says the chain must be approved for overhead lifting by the chain manufacturer. I no none that say their grade 30 can be used for overhead lifting. And there are chains, like SECOAs STC and Clancy's Alpha Chain that those manufacturers approve for overhead lifting.

Don't quote the annex because the annex is explanatory and not requirements.
 
Keep in mind this is for the chain only, the eye bolts and such still have issues.
Correct - I was addressing the chain only. The forged steel is in 3.18.3.1, not 3.18.3.3, where its repeated for the wire rope clip.

And with sincere apologies for being picky, but "Only rated and forged eye bolts can be used for overhead lifting" could be misleading. Many things can be used but if eye bolts are used they shall be rated and of forged steel. Not other forged materials.

So, sorry to be picky but you have to be with standards. Best to quote and not summarize. You just can't imagine how many people review these before published for every nuance and possible interpretation - and still some goofy things get by.
 
Don't quote the annex because the annex is explanatory and not requirements.

Okay, fine point. The annex is not part of the standard's requirement.

I don't recall myself ever needing to use chain in a single load path, although in my space the main curtain's batten is dead hung in such a way, so this is really the first time I've thought about this.

If we just imagine that one wants to not only be free of liability but also avail oneself of the explanatory guidance of the experts in the Rigging Working Group, then one would try to decipher and adhere to the annex, right? Reading it again it makes less sense to me and my first reading was indeed incorrect.

The annex says the first of two options for a single load path application is to use chain rated for overhead lifting (and presently that means grade 80+). Then the second option is to use chain with a manufacturer's certification for the intended application (presumably an application other than overhead lifting, like in OP's case). But wait--that certification is needed "if its material properties and strength characteristics do not meet or exceed that of Grade 30 Proof Coil chain." So if that is the case then as long as the chain is up to grade 30 specs, it need not be certified for the application? There seem to be contradictions between this explanation and the actual standard. The annex seems to say you can for instance use grade 30 chain with no certification for the intended application, but in reality the one thing the actual standard requires is that it "be certified in writing by the chain manufacturer as suitable for the intended application." And with that the only requirement of the standard, why even bring an overhead lifting rating into it as they do in the annex? Golly, help me out here!
 
I can tell you we are addressing this exact issue currently with the next document in the E1.4 family, which is about statically suspended rigging. We are attempting to clarify the "overhead lifting" definition so we can hopefully be able to make it easier to know when/if you can use grade 30 proof coil chain in our applications. To do so requires a lot of discussions with the manufactures and their relevant trade associations. Not a fast process at all. But hopefully we will be able to give guidance when the standard is published. And for those about to ask, it will probably be at least at another 18 months plus before its published. As soon as the first public review happens I will make sure you all know so you can get a look at it.
 
I can tell you we are addressing this exact issue currently with the next document in the E1.4 family, which is about statically suspended rigging. We are attempting to clarify the "overhead lifting" definition so we can hopefully be able to make it easier to know when/if you can use grade 30 proof coil chain in our applications. To do so requires a lot of discussions with the manufactures and their relevant trade associations. Not a fast process at all. But hopefully we will be able to give guidance when the standard is published. And for those about to ask, it will probably be at least at another 18 months plus before its published. As soon as the first public review happens I will make sure you all know so you can get a look at it.

Thanks for that. I'm getting rather sick of this whole discussion. I don't really care which way it falls, lets just make plan and go with it.
 
In reply to Colin, I agree the annex note is contradictory. In my opinion, grade 30 shall not be used in any overhead lifting load path. The National Association of Chain Manufacturers are quite clear on this and I believe OSHA also is not too unclear that chains used in overhead lifting must be alloy chains. Trying to spin what "overhead lifting" means (really? Seems clear and will to a jury); or otherwise over rule or dismiss what the NACM says is silly. What should have been done for the first edition of E1.4, where I was the voice and main proponent of respecting what the NACM said and what the standard does say now (screw the annex), was approach and work with the NACM to allow grade 30 to be used. Perhaps NIH and concern for relative anatomical dimensions prevented this but it was the only logical way out. In the mean time, SECOA and Clancy (and I think I heard some one else recently) solved it by developing a workable alloy chain product.
 
I'm pretty clear on what constitutes overhead lifting, and that the application in question is not. What is wacky about the current E1.4 (and especially this annex entry) is that it seems to want to require, or at least suggest as an acceptable example, the characteristics of overhead lifting rated chain for purposes other than overhead lifting. So, the term "overhead lifting" gets used a lot where it is not truly in play and better language might be something like "alloy" or whatever communicates the material properties and strength characteristics of chain rated for overhead lifting. The design requirements need to be de-linked from the definition of the overhead lifting application.

Plus, to me the origin of the confusion about what is and isn't overhead lifting is the term itself. It is easy for someone approaching the issue for the first time to look at a counterweight set, read the words "overhead" and "lifting", and think that those words must describe trim chains on a moving (lifting) batten. A little more digging clears it up, but it seems like it would be more clear to alter the term to acknowledge the key concept of "freely suspended" right off. Then in the definition of terms, a little more about the definition of "freely suspended". But that's the NACM writing that definition, right?

Right now the best plain language explanation I know of comes from JR Clancy and even they use iffy language like "we think Grade 30 Proof Coil Chain is acceptable [as trim chain] from an engineering perspective." Some people are going to be twitchy about it until someone changes "think" to "know" and adds clarity to the standard. Glad we have some CB members who are involved in the process. What a task...
 
Right now the best plain language explanation I know of comes from JR Clancy and even they use iffy language like "we think Grade 30 Proof Coil Chain is acceptable [as trim chain] from an engineering perspective." Some people are going to be twitchy about it until someone changes "think" to "know" and adds clarity to the standard. Glad we have some CB members who are involved in the process. What a task...

At the same time they also use proof coil 30 chain for dead hanging... http://www.jrclancy.com/Downloads/ChainforTheatricalUse.pdf

It is apparent that those in the industry want to see this cleared up. If we can use a chain a 1/3 of the price to dead hang battens in high schools that would be great.
 

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