Im an old school electrician and was stupid enough to get into a conversion with my supervisor who is not an electrician about arc flash and shock hazards.He now wants me to fabricate guards to mount over the exposed fusing lugs in all the starter buckets and panels in the plant.
Not being up on this sort of thing I would think the manufacturer should be consulted before i start fabricating anything in the name of safety.I would also imagine there are specific materials and thicknesses that would have to be used.I have not started to investigate the issue but opinions would be greatly appreciated.Ill run this by CCS but i want to at least have a clue what im talking about.On a side note they are to cheap to buy a new code book if you an believe that.
You might want to show him some videos of arc flash events and then ask him if he really thinks that homemade guards would do anything.
Perhaps the video of an MCC door being blown out would work...
https://www.youtube.com/watch?v=Sk7uVKC7r_I
Exactly what im thinking.He uses the term finger less and says they did it in Brittan where he is from.He also made a comment that since i don't know anything about it that the Canadian license is worthless and that im not qualified to do any work.To be honest.I don't think he qualified to sweep the floor behind me after im done doing my work.
This is a hospital engineering department run by an outside contractor who refuses to adopt arc flash regulations.They wont buy the electricians code books and had a loto course in August only because it was mandated.They still have not bought us our locks so we are forced to either buy and use our own loto locks or more often than not use a commonly keyed lock.Regardless the lock gets either cut off or someone takes it.
The best part is that there is no written electrical policy The the floors often call down to have patient electrical equipment brought from home "inspected"Since there is no policy there are no standards to inspect for.I have brought this all up and he says it coming.It has been "coming"for the last 3yrs.
This new pissing match started because the thermografic report came back and i have a few "hot" jobs to do with no PPE. Dont you have to have the rated PPE to live test and troubleshoot equipment? This has been going on since this new management took over 3yrs ago.I have flat out refused the work and was instructed that as an essential service work refusal on the grounds of safety is restricted by law if patient care is compromised. I have 4rys to retirement and i dont think im gonna make it.Ill either be dead,in jail or in the nut house.I swear to god im working in the twilight zone.Im a multi-ticket tradesman who has never seen anything that even comes close to this in 32yrs of working in trades
Any options or suggestions would be greatly appreciated.
thanks
frank:
He must mean "finger safe"; preventing contact with live exposed parts.
IMHO, this is not relevant to PPE/arc flash, etc. It will add either particles, pieces, gases, or more projectiles in the event of an arc flash incident.
Not having proper PPE supplied by the employer will result in an issue with OSHA on this side of the border, OSHA fines are $$$$$$, and proper PPE/LOTO, etc is a heck of a lot cheaper.
Do you have a government version of OSHA in Canada??
Your right.There is no way im improvising guards that are not manufacturer approved for the gear.I also find it a little unsettling sticking probes in holes to test voltage when i cant see where they are going on the new equipment we have.
We have the Ministry of Labour here and use Z642-15 which basically follows one cycle behind NFPA 70E.
Its a bad system because building owners who don't have employees working above 240v do not have to adopt arc flash regulations.As a result many will say they dont but then tell the employees to fix equipment that exceeds 240v.If the electrician gets hurt the managers say they didn't know the rules were being broken
What they do is tell you to go fix it and dont print the work orders or cancel them after the job is complete if you complain.
We have mostly 600v systems in my building and its all automated with Johnson Controls Metasys M5. I have installed all of it and maintain it yet they deny its being done if asked.The problem they have in doing that is that Johnson Controls requires specialized electricians to work on it because the design requires that the low/extra low voltage barriers must be crossed.Essentially there is 24v devices in the same compartment with the 600v and run out to extra low voltage controllers so the wire has to be in pipe or special ordered from Belding.Management seems to think they can hide the fact that i work above 240v yet there are only three buildings in the city using this type of automation and all are using staff electricians to install and maintain the systems.There are no contractors who do this work in a city of 250000.The inspectors know what im doing and allow it by special permission as long as im the only one doing it.
I think thats why he wants guards put up He seems to think i can work with much less or no PPE if we get caught and hes dead wrong.
frank:
Think about this:
" hes dead wrong "
But, the actual person (perhaps you) can be the one in the flash, and be injured, disabled, or ......!!!!!
This guy's thinking is going to get someone killed...
From Wikipedia:
As an example of the energy released in an arc flash incident, in a single phase-to-phase fault on a 480 V system with 20,000 amps of fault current, the resulting power is 9.6 MW. If the fault lasts for 10 cycles at 60 Hz, the resulting energy would be 1600 kilojoules. For comparison, TNT releases 2,175 J/g or more when detonated.
Thus, this fault energy is equivalent to 380 grams (approximately 0.8 pounds) of TNT.
FYI, a WW2 hand grenade contains 57 grams of TNT.
I wonder how safe a soldier would have felt behind a homemade piece of Lexan.
There are a lot of good videos at Bussman.com and also at Square D websites.
Amazing that the management guy is confusing 'finger safe' with arc flash!!
Yes it is amazing.He thinks guarding the exposed energized part will allow us to work without or at greatly reduced arc flash PPE.An improvised guard is just another object to fumble around with and I dont even know how you would mount it in a safe manor.I can see it all failing apart in continuously cycling starter bucket,something manufactures take into account im sure.Its also my understanding that dead fronts and bucket doors are not rated to withstand an arc flash event unless labeled as such.
I spoke an inspector about it,got a glazed over look and an invitation to the ESA arc flash course to the tune of $400 plus tax.
I didnt think to look until ghost307 pointed it out but I'll send him to the Wikipedia link...That should thoroughly piss him off.lol
This supervisor is known to lie his ass off about all kinds of things.He tried telling me the code book is no longer in paper print and has to be purchased on CD for over $1000 not more then ten minutes after i found it for $120 on the CSA website.The CD was around $350 i think.
I could start emailing the higher ups in the organization but then i may as well ware a target on my back and give him a gun.Im at a total loss on what to do at this point egos are getting in the way and thats a dangerous thing.
At least Im signed up for the course now and paying for it myself.There is language in my job description stating im entitled to all training in my job description however its just not worth trying to deal with him.
Frank,
I may be wrong here, but is Lexan self-extinguishing if it catches fire?
Also, what are the temperature limits of this material, if it is anything like Plexiglass, it softens when you heat it up, that's how they form it to build things out of it.
What I'm trying to say here is that while there shouldn't really be a lot of heat in any electrical enclosure, but that needs to be taken into account if you are using thermo-setting plastics.
Just a thought off the top of my head.
Trumpy,
The numbers are all over the place.Thermal resistance is 250F and dialectic strength is 400 ohm cm.It is self extinguishing but thats from one of many data sheets the numbers are relative to the particular manufacture.
My concerns are.
-Added electrical component heating
-How it will react in an arc flash/blast situation
-how do you mount/form it in the tub and whats required clearance from the energized parts.
- will it attract dust,filings,and fluff over time
-is it going to rattle apart around equipment such as high cycling starters.
-will this affect the equipment CSA listing as its an improvised alteration and not manufacture approved.
-Liability in the even of an accident investigation.
The main concern is that after talking to many electricians no one has thought of or attempted fitting unapproved guarding in such a way.
Any guarding that is an original equipment part has been engineered and tested to a set standard.Once CSA has approved and listed it further modification is asking for trouble.
I also don't understand the point.It will create an obstruction when making a visual inspection,trap any garbage that falls between it and the fusing OR buss,obstruct air flow and heat dissipation.It will have to be removed in order to troubleshoot and re torque screws which i normally do on all equipment that i work on.
To me this seems like a bad idea.Am i missing something?
Thanks
Frank,
Your concerns are not un-warranted either, as you've mentioned yourself, this whole thing involves the installation of unapproved modifications to this equipment.
In saying that though, we use clear plexi-glass covers held in place with insulated studs on a DIN Rail and these have a heap of holes for getting test probes in to fault-find equipment and this also ensures adequate air circulation.
Having things fall into the live busbars or other equipment is not really an issue, because of the way the shields are formed, they have a 45 degree angle at the top and bottom of the part that is held to the studs.
I wouldn't worry too much about getting hit with the makeshift plexiglass cover...melted or not.
The initial blast will probably kill you if you're not wearing the proper PPE.
Ghost,
This is true but i just find it insulting to be asked to add shrapnel to my own IED.I told him to go look at the videos and he just stood there and blinked at me like he usually does.No matter i told him to stick it......not doing it....ever.
Trumpy,
These are older 600v 40hp starter buckets that are also populated with extra low voltage automation.The fusing and O/L'S are brought to as close to FLA as possible on the inspectors orders to get special permission.Heat can be and has been an issue.
The fuse holders stand 8 inches tall on idolators and they do not have a molded base that extends out past them that would act as a stand off.There is also little room if any for mounting the lexan and the starters are even worse.This is nothing like covering Din rail mounted terminal strips to which i see the logic.If i could post a picture i would.