# Questionable Rigging



## stgtech91 (Jul 19, 2015)

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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## Footer (Jul 19, 2015)

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.


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## RickR (Jul 19, 2015)

"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.


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## stgtech91 (Jul 19, 2015)

[/QUOTE]


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## Footer (Jul 19, 2015)

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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## stgtech91 (Jul 19, 2015)

Footer said:


> 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


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## egilson1 (Jul 19, 2015)

Is this a staticky suspended system?


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## Footer (Jul 19, 2015)

stgtech91 said:


> 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.


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## Moose Hatrack (Jul 20, 2015)

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)


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## StradivariusBone (Jul 20, 2015)

Moose Hatrack said:


> 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)



https://en.wikipedia.org/wiki/Hyatt_Regency_walkway_collapse

Wow, that is the stuff of nightmares. I'd never heard of that accident before.


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## Colin (Jul 21, 2015)

Footer said:


> 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.


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## BillConnerFASTC (Jul 21, 2015)

This application is not overhead lifting. It's static, no impact loads. Grade 30 is fine for dead hung - just check design factor but hard to imagine it's not way over 1:8.


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## BillConnerFASTC (Jul 21, 2015)

Colin said:


> 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.


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## Footer (Jul 21, 2015)

BillConnerASTC said:


> This application is not overhead lifting. It's static, no impact loads. Grade 30 is fine for dead hung - just check design factor but hard to imagine it's not way over 1:8.



Keep in mind this is for the chain only, the eye bolts and such still have issues.


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## BillConnerFASTC (Jul 21, 2015)

Footer said:


> 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.


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## Colin (Jul 21, 2015)

BillConnerASTC said:


> 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!


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## egilson1 (Jul 22, 2015)

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.


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## Footer (Jul 22, 2015)

egilson1 said:


> 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.


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## BillConnerFASTC (Jul 22, 2015)

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.


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## Colin (Jul 22, 2015)

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...


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## Footer (Jul 22, 2015)

Colin said:


> 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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## BillConnerFASTC (Jul 22, 2015)

Colin said:


> 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...



I'm not clear on what you are saying but I strongly believe that a trim chain is an example of overhead lifting as used by the NACM, who write the standard for chain and who coined the term overhead lifting, and thy and their members individually say trim chains are an overhead lifting application and that grade 30 is not approved by the chain manufacturers for trim chains when used for overhead lifting.

I think what you are referring to was written by someone trying to rationalize what they had been doing, and interpreting the NACM standard without contacting NACM. I contacted them and spoke with the executive director as well as the members of the committee that writes the standard, mostly tech people from the manufacturers, and that is what I base my opinion on. I've expounded many times on the 'freely suspended" term and what you reference ignores what the NACM says it mean, and it's their term.

This can become very personal. I have been libeled in public meetings by some who disagree, claiming I said things I did not say and which I could prove by recordings. Simply a lot of people don't want to admit that what they have done should not be done. If the prohibition is justified or not, I'm not commenting, but technically you cannot use grade 30 chain for a trim chain application when it used to lift (raise and lower) loads over (peoples') heads.

You're darn right they use iffy language. I hope you don't feel that way about what I say. And just to be sure, do not use grade 30 chain as trim chain material for loads over head on a stage which are lifted by manual or motorized rigging.

It is like $50 per lineset to use a chain that is so $50 for manual at $7000-8000 per set or motorized for $18,000-50,000 or more per set. Why bother trying to defend it for that puny amount of money?


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## Colin (Jul 22, 2015)

BillConnerASTC said:


> I'm not clear on what you are saying but I strongly believe that a trim chain is an example of overhead lifting as used by the NACM, who write the standard for chain and who coined the term overhead lifting, and thy and their members individually say trim chains are an overhead lifting application and that grade 30 is not approved by the chain manufacturers for trim chains when used for overhead lifting.
> 
> I think what you are referring to was written by someone trying to rationalize what they had been doing, and interpreting the NACM standard without contacting NACM. I contacted them and spoke with the executive director as well as the members of the committee that writes the standard, mostly tech people from the manufacturers, and that is what I base my opinion on. I've expounded many times on the 'freely suspended" term and what you reference ignores what the NACM says it mean, and it's their term.
> 
> ...



Bill, I trust nobody's view on this more than yours. But then we have a large portion of our industry, including leading rigging companies like JR Clancy and Sapsis, seeming to say something different, so I'm just trying to get to the bottom of that disconnect because until we do it is going to be darn near impossible for a lot of end users to push your recommendations through their bureaucracies. It shouldn't take finding you on a forum to get this right, but that's about all there is right now. I'm concerned with the real-world consequences of this as an end user who has neither your intimate knowledge of the standard-making process, nor your direct contact with the NACM. Does everyone really need to interview the NACM executive and committee in order to understand the standard? Aren't standards written in order to eliminate that need? Clearly it isn't working that way, and whether it is because people are willfully ignorant, stupid or something else, something should be done to reduce the possibility of erroneous interpretations becoming so pervasive. While it may not be the NACM's top priority or responsibility to intervene with an unsolicited public clarification of their definition of overhead lifting, it sure would be helpful. Bill, are you aware of anything to that effect? 

JR Clancy has put their (wrong, I guess) interpretation in writing. To be fair, I haven't heard it explicitly from Sapsis, but Bill Sapsis himself did my last inspection and was fine with our grade 30 trim chains, and some that aren't even stamped. The argument that you are at odds with, which like I said before is too tenuous for my comfort, but which seems to be in line with every counterweight system installation I come across, is that a chain is only considered to be in a lifting application if it is being lengthened or shortened by mechanical means, as in a hoist. The other part of the argument is that 'freely suspended' involves a possibility of torsional stress as in a single point from a crane for instance. 

So using that argument, the counterweight system designer tells the end user that their grade 30 trim chains don't fall under the overhead lifting definition, and one of the most respected ETCP riggers out there doesn't say peep about them during inspection. Meanwhile, from what you say it sounds like nobody is backing any of this up by actually asking the NACM. That part I didn't know until now.

It would be really nice if all the experts would get together on standards and definitions that provide absolute clarity for our industry's common applications, because otherwise end users like me and the OP just don't have enough to back up (or refute) our less-expert interpretations.

Save for running into generous experts like you, Bill, people are naturally likely to trust what the system designer says. It may be some comfort liability-wise to have Clancy standing behind their proof coil trim chains, but if the NACM says they're no good then there is at very least a moral dilemma for the hundreds? thousands? of facility managers who currently have proof coil trim chains in the air.

What if a TD wants to secure funds to follow your recommendation to switch to overhead lifting rated trim chains (with my regular budget $50 per set is actually prohibitive without a multi-year plan)? If I need to go ask for more money and my president, provost or trustees want me to prove the necessity (they will) then it is the written word of the company that designed the system versus the NACM who are not specifically theater rigging experts. It is indeed infuriating that the NACM is not being asked about their own definition, but try convincing the average academic bureaucracy that the company they already picked to do the original system and that devotes all its time to specifying theatrical rigging is wrong, and some other body they've also never heard of is right...


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## BillConnerFASTC (Jul 22, 2015)

Good post - not because you flatter me but because you make some good points.

First, in terms of safety and comfort - I make a note of it on inspections but am clear that it is the littlest of causes for concern. This is a technical issue created by OSHA - which the NACM standard was a response to. I doubt if a grade 30 trim chain has ever failed. (Though I just learned of what I would consider an equally unlikely failure - so now I don't trust anything just because we've always done it that way.)

I think what the NACM says is clear. Read it and decide for your self. (OK - its been 2-3 years for me and could have been updated so I should be careful.) I only went there as a result of relentless challenges and to rebut the baloney that people were saying and publishing about "freely suspended" and "overhead lifting". I was "sure looks like grade 30 can't be used so lets find out" and others did not want to know or did not want to know for sure what they did not like. My feeling is at least have the courtesy of asking the committee that wrote something what it meant instead of publishing the interpretation that fits your wishes and ignoring them. (And frankly I believe the NACM standard could be changed with the proper approach and diligence to allow the use of grade 30 - probably in a single load path. I offered to do it - for a fee. No one bit.)

Clancy does play it cagey - they simply make available someone else's report, and are not responsible for it. They also stand to profit by selling Alpha Chain instead of Grade 30. (The $50/set is more an approximation of the difference in a new install - not the cost of replacing.) Hey, Clancy did the work to show safety bolts in trim chains were not only redundant but could be a negative - and that changed - but some people still decry that.

System designer is vague but is that someone who is paid by the vendor or someone who is independent of the vendor? Actually quite a few theatre consultants don't allow grade 30 today. 

As far as everyone getting together - well - kind of did for E1.4. I don't know what you find unclear in the standard. I understand the annex is confusing. And the draft allowed grade 30 and I led the case against it and convinced the majority of the committee to agree. Also, E1.4 is not a law. Its just a standard written by people who got together and because they claim to have adhered to a particular process, it has an ANSI designation. Sorry - but read my article on codes versus standards - which was written in response to an error plagued article written by Clancy employees for Clancy and was just flat out wrong. 

At the end of the day, this is a deadly boring subject. But these things affect what I do planning and designing auditoriums and stages and I think the regulations and promulgated standards should be as clear and science based as possible.


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## BillConnerFASTC (Jul 22, 2015)

See what stgtech91 started? All his fault.

Not really. Just trying to keep it light.


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## Amiers (Jul 22, 2015)

I enjoy reading these threads. It gives me something to look forward into the future past this little show I run and maintain.


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## Colin (Jul 22, 2015)

BillConnerASTC said:


> I think what the NACM says is clear. Read it and decide for your self.



The issue I have with the NACM's overhead lifting definition is that it uses the term "freely suspended" without going into what that means (at least not anywhere I've been able to find in their Welded Steel Chain Specification). This allows for interpretations like Clancy's idea about the trim chain application not being freely suspended because, as they put it, "by standard definitions, it [freely suspended] implies a concept of hanging something in an unrestrained manner or without restrictions or limits." If NACM were more specific about the condition of being freely suspended, then it would be harder to misinterpret.


BillConnerASTC said:


> System designer is vague but is that someone who is paid by the vendor or someone who is independent of the vendor? Actually quite a few theatre consultants don't allow grade 30 today.



I'm using as an example personal experience with Clancy designing the systems in, I think, all three fly houses I've spent significant time in. Didn't mean to suggest everyone specifies grade 30 of course, but I haven't seen anything else myself. Three isn't a big sample size, but I'd wager a poll would turn up a sizable percentage of existing installations with grade 30. Just a guess, because it is cheaper than alloy, and Clancy for instance says it is okay.


BillConnerASTC said:


> As far as everyone getting together - well - kind of did for E1.4. I don't know what you find unclear in the standard. I understand the annex is confusing. And the draft allowed grade 30 and I led the case against it and convinced the majority of the committee to agree. Also, E1.4 is not a law. Its just a standard written by people who got together and because they claim to have adhered to a particular process, it has an ANSI designation. Sorry - but read my article on codes versus standards - which was written in response to an error plagued article written by Clancy employees for Clancy and was just flat out wrong.



E1.4 says "trim chain assemblies shall be fabricated of chain approved by the manufacturer for the application." What application? Overhead lifting? Then we're back to the issue I have with the NACM's definition. If one convinces oneself that trim chain is not doing any overhead lifting, then what manufacturer approval does one need in order to follow the standard? The standard needs to say "trim chain assemblies shall be fabricated of chain approved by the manufacturer for overhead lifting" if that is what it intends. If there is a discretely defined application called "counterweight batten trim chain" then the standard should explain that application so that manufacturers can determine if their products are approved for it.

I've read your article on codes and standards, albeit some time ago. While the standard isn't law, it is nevertheless something to aspire to, don't you think?


BillConnerASTC said:


> At the end of the day, this is a deadly boring subject. But these things affect what I do planning and designing auditoriums and stages and I think the regulations and promulgated standards should be as clear and science based as possible.



Sooooo deadly boring! But important not just to you but to me as an educator who spends a lot of time pointing out to students that they may need to reconsider what is truth and what is, as Stephen Colbert said, "truthy." There's a lot of room for truthiness between E1.4 and NACM's definition of overhead lifting, as evidenced by the widespread confusion we are both familiar with.


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## BillConnerFASTC (Jul 22, 2015)

Freely suspended seems pretty clear. If the load is anchored or if there is another force acting on it like wind its not freely suspended. If the load is just hanging there, only affected by gravity, it is. No one questioned this until grade 30 trim chain advocates starting trying to rationalize their proclivity.

I have no further comment on vendors as designers.

I don't see the confusion on the application. Do you think a trim chain is somehow not overhead lifting?

I helped write an office standard for cad layers. Should everyone aspire to it? I guess just because something can be called a standard doesn't make it something all should aspire to IMHO. With NFPA standards, much effort is given to minimum requirements for safety, and avoiding "design" considerations. I believe E1.4 crosses that line too much.


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## Colin (Jul 23, 2015)

Okay, last post in this thread for me, but I'll read anything more from Bill or others with interest.


BillConnerASTC said:


> No one questioned this until grade 30 trim chain advocates starting trying to rationalize their proclivity.



Right, and they succeeded in so many minds! That rationalization is even cited multiple times in what I think has been, maybe until I hijacked this thread (sorry), the primary discussion of trim chain on CB. Does this contagion not irk the standard writers? It irks me as an end user who has inherited a system with trim chains specified according to that rationalization. Of course "freely suspended seems pretty clear" to you, an accomplished authority on these subjects, but other people may willfully skew it in a different direction, and still more people will accept that skewed perspective because it came from a trusted source and _seems_ to make sense to them.


BillConnerASTC said:


> I don't see the confusion on the application. Do you think a trim chain is somehow not overhead lifting?



Well I started out on your side of the issue some years ago but the 'rationalized proclivity' as you say has made me doubt my original understanding. Now I'm inclined to think what you think because for one thing you surely are more equipped than I to make that determination, but the confusion will be out there whether for me or any number of other people until the standard actually says that trim chain is indeed an overhead lifting application. The core issue here is that "grade 30 trim chain advocates" have been able to conjure 'evidence' that trim chain is excluded from the definition of overhead lifting. That has happened, regardless of whether you or I think it is correct, and there are people out there who believe the hype. The failure in E1.4 to assert that the trim chain application is indeed "overhead lifting" (those two words have to be used or this specific assertion is not made) gives cover to the grade 30 proponents.

If the standard writers disagree with said hype, then they could clarify their position by changing the language to say something like "trim chain assemblies shall be fabricated of chain approved by the manufacturer for _overhead lifting_" or other wording that clarifies that they believe trim chain is in fact an overhead lifting situation. It not only clarifies their position, which I suppose should be the primary objective, but also pulls the rug from under those like Clancy who don't exactly reject the NACM's definition of overhead lifting but instead argue (yes, without asking NACM) that the NACM doesn't intend a trim chain to fall within the definition. If E1.4 were to outright say that they believe trim chain specifically does live within the definition of overhead lifting, then it would be much more obvious that one can't use grade 30 trim chain and be in agreement with E1.4.


BillConnerASTC said:


> I helped write an office standard for cad layers. Should everyone aspire to it? I guess just because something can be called a standard doesn't make it something all should aspire to IMHO. With NFPA standards, much effort is given to minimum requirements for safety, and avoiding "design" considerations. I believe E1.4 crosses that line too much.



Sure, meeting a standard isn't necessarily the ultimate achievement, but I can't imagine anyone aspiring to sub-standard rigging. In the grand scheme of CAD one might say there are no sub-standard but only non-standard methods (unless you're ignoring your company's adopted standard, which would probably get you in trouble with the boss). In rigging, it seems clear to me that alloy chain meets a higher standard than proof coil, and that is desirable.

Always grateful for your engagement.


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## BillConnerFASTC (Jul 23, 2015)

I agree it should be cleared up. Either accept and make clear that trim chains must be made of alloy chain or work with NACM and OSHA to have them agree grade 30 is acceptable. Don't try the "we no better what you product is acceptable for than the manufacturer does" as has been the case. Having two different and conflicting definitions for the same term in two standards that both apply is also not the right path.


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## StradivariusBone (Jul 23, 2015)

As I understand it the main difference between G30 and G80 is low carbon steel vs. alloy steel and that alloy steel is pound for pound stronger than the low carbon. Why then if you're within your safety ratio is it a bad idea to use G30? Is it in how it responds to the shock loading or its elasticity in moving a load? Would the lower carbon be more susceptible to catastrophic failure in these circumstances? I'm not throwing gas on the fire, I'm just curious as to the physical reason some vote different ways on this issue as I'm not knowledgable enough on the subject to form an opinion worth putting out. Are there documented failures of G30 chain in overhead lifting situations?


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## BillConnerFASTC (Jul 23, 2015)

I'm not sure Strad - but I have emphasized that it's what is written by OSHA and NACM that is the issue, and not the engineering merits. I do believe that the testing or testing sampling is a little more rigorous for the alloy chains. BTW Clancy's Alpha Chain and SECOA's STC are grade 63 and approved by the manufacturer for overhead lifting and are much easier to work with than grade 80, and less expensive than grade 80. SECOA wanted to solve the issue so had an alloy chain developed that has the physical - dimensional - characteristics of grade 30; rightful claim to being the manufacturer; and satisfying the OSHA requirements. Clancy followed or paralleled this a little later, and one upped SECOA by having it blackened where it was made.

But based on my understanding - that the probably knee jerk reaction of OSHA after an incident and subsequently NACM in response to OSHA, both of whom probably never having heard of trim chains and theatre rigging - I had optimism it could be worked out to allow grade 30 - with the manufacturers blessing - for trim chains. Whether impatience, arrogance, or some other reason, there was not consensus or the interest and will in the entertainment technology to go that route. I had even casually suggested that for not a large fee, I would be willing to do it as a consultant - meet with the individuals and bureaucracies, educate them on the issues, pint out the engineering and overall design and high or very high design factors applied, and in general be a code consultant, and get it done.

So ultimately two private for profit businesses basically solved the commercial side of this in large measure when government and association committees could not. I know which one I choose. Others may choose the other which might or might not comply with standards and laws (OSHA).

I did just tell a client that they really ought to replace the swing chain and snap hook trim chains, and while doing it use the alloy chain. Same client has other stages with grade 30 and replacement was a low priority. And quickly I'm going to get back into my reports versus a vendor's report, which I believe have very different goals, so I'll stop here.


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## gafftaper (Jul 28, 2015)

Colin said:


> I've read your article on codes and standards, albeit some time ago. While the standard isn't law, it is nevertheless something to aspire to, don't you think?



I think I was at a session of USITT this year where they made this point: Our industry standards are voluntary and not law, but they can easily become law. Let's say someone is injured and there is a law suit. Lawyers will scour the universe for every bit of information they can find. They will eventually come across Plasa technical standards. The standards will be used as part of the trial. Once that case is decided, those standards become part of the legal precedent for who is at fault in a particular situation. From that day on, they are effectively law without ever being officially made laws.


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## BillConnerFASTC (Jul 28, 2015)

gafftaper said:


> I think I was at a session of USITT this year where they made this point: Our industry standards are voluntary and not law, but they can easily become law. Let's say someone is injured and there is a law suit. Lawyers will scour the universe for every bit of information they can find. They will eventually come across Plasa technical standards. The standards will be used as part of the trial. Once that case is decided, those standards become part of the legal precedent for who is at fault in a particular situation. From that day on, they are effectively law without ever being officially made laws.


Read my article but your talking about case law, and that can be reinterpreted and overturned by a good lawyer and different experts, and its meaning is never made clear or the same. Statutory law on the other hand is much less fickle. Big difference.


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## gafftaper (Jul 28, 2015)

BillConnerASTC said:


> Read my article but your talking about case law, and that can be reinterpreted and overturned by a good lawyer and different experts, and its meaning is never made clear or the same. Statutory law on the other hand is much less fickle. Big difference.



True. The point they were making in the session was just because the standards are not law, doesn’t mean that they are optional. If you know that the standards exist, you don't follow them, and someone gets hurt, you will be held accountable to the standards in court.


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## BillConnerFASTC (Jul 28, 2015)

gafftaper said:


> True. The point they were making in the session was just because the standards are not law, doesn’t mean that they are optional. If you know that the standards exist, you don't follow them, and someone gets hurt, you will be held accountable to the standards in court.


If the standard is believed to be good. Just because it exists does not make it automatically creditable. Nothing does that except being made a law.


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