Commercial is sure different!

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George Stolz

George Stolz

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Location
Windsor, CO NEC: 2017
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Service Manager
I took a few pictures in the hospital I'm working in, thought I'd share a little slice of what I've been up to since my change from resi to commercial, and I saw an avenue or two for code discussion along the way.

Do you consider a cut-in troffer hole acceptable to make junction boxes accessible?

Hospital013.jpg

In the hard lid of this emergency room, we have junction boxes for the lights and receptacles above. They will be accessible after the fact by removing the troffers next to them. Do you consider this code compliant?


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Here is the pipework I did over the ER ceiling. Actually, a couple guys started, and I had to finish it off. If I had taken pictures before drywall was completed, you'd be able to see that I had to ride the wall, and then kick into the wall before 90-ing down to the receptacles - to keep the "lanes" open for more conduit.

I actually had to remove and rework some of the other's work simply to make more room. Eventually the room ran out, and fortunately by that point there were only a few more conduits to go, so they could roll out away from the wall and bypass the traffic altogether.

I've found trying to share the same cramped space with tinning, med gas and other plumbing has been an incredible challenge at times. For another example, check out the path to the electrical room:


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The cable tray is exactly 4" above the bottom of the grid ceiling. The doorway is roughly the same size as the electrical room at the door, as seen in this picture. Unfortunately, the rack of homeruns is quite wider than that. :D

I wish I had taken some picture's of Ron's rack that had the 30+ home runs on it. It was in an area I couldn't get to on Friday. He's a master with mostly industrial experience, and his conduit work is extremely clean. I think at one spot he had 20+ 3/4"s with over a 2' kick, and none of them were the slightest bit out of line. :)

My poor rack (seen here just outside the electrical room) ended up having to be contorted quite a bit to find my own way there.
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georgestolz said:
Do you consider a cut-in troffer hole acceptable to make junction boxes accessible?
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Yes. Absolutely no different than taking a recessed can down out of the plaster frame to access its j-box. There are some places where I've had to removed a framed troffer in a hard lid to crawl up inside there and walk on top of a wall top plate for dozen of feet to get to what I needed to work on. No different than any other scuttle hole door. Just happens to also be a lighting fixture. Accessible doesn't mean easy or fun.
 
georgestolz said:
Here is the pipework I did over the ER ceiling. Actually, a couple guys started, and I had to finish it off. If I had taken pictures before drywall was completed, you'd be able to see that I had to ride the wall, and then kick into the wall before 90-ing down to the receptacles - to keep the "lanes" open for more conduit.
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Here's something they did on a recent hospital job, so that it was easier to keep track of the ratings of the wall assemblies for penetration. They spray painted this every 12 feet or so above the suspended ceiling line:

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georgestolz said:
Small world, they did the same thing at the one I'm working in :cool:

I wonder if maybe it's a building code, or just considered a good idea?
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I don't know. I've only ever observed this procedure in health care occupancies.
 
mdshunk said:
Here's something they did on a recent hospital job, so that it was easier to keep track of the ratings of the wall assemblies for penetration. They spray painted this every 12 feet or so above the suspended ceiling line:

smoke.jpg
Click to expand...

I hope there was some securing of the cabling method after the picture was taken.
I have noticed of late that the commercial work ceilings could use some more attention to this issue.


George
Some are meant to bend pipe, and some are not. My junk pile would attest to the fact that I was not one of those skilled at pipe work. If you really want to learn, and have a good mentor, you will learn.
 
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georgestolz said:
Do you consider a cut-in troffer hole acceptable to make junction boxes accessible?
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Absolutely, agreed with Marc.


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In this pic, I notice that the fire-caulking is simply used as a sealant, but I bet it's not done according to UL specs for the product and the penetration.

If this is a fire-rated wall, the fire barrier is supposed to be applied in a method that allows it to expand and fill the penetration as the conduit burns away.
 
peter d said:
George, why is all that piped? Are you not allowed to use MC cable?
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:grin: You love MC, don't you Peter? Here's a query from one hospital's plant operations manager. He apparently doesn't like spaghetti.

Do you allow the use of so-called "hospital grade" AC cable in your hospital or healthcare facility?

We recently started doing this but only for use within a room. No homeruns in AC. All homeruns are piped in EMT to the room then AC whipped from there. The thinking here is you can still get new circuits close to the area they are needed without running more pipe, you don't have the spaghetti mess in the corridors and in the electrical rooms that come with AC and when the inevitable renovations come it will make it a little easier to move walls, and finally, it is cheaper due to the labor savings.

My only fear is that once this practice has been started it will get out of hand if not policed closely and we will end up with the spaghetti mess in the end.
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LarryFine said:
th_Hospital008.jpg

In this pic, I notice that the fire-caulking is simply used as a sealant, but I bet it's not done according to UL specs for the product and the penetration.
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Can you elaborate? I try to fill in as best I can - I just trowel off the excess around the exterior of the hole to finish it up a bit.
 
macmikeman said:
Hey George, commercial is generally a lot more fun to work, agreed?
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There is a greater sense of accomplishment at the end of the day. Bending pipe is fun. I enjoy having to apply more thought into what I'm doing, some things just come automatically with NM that require some planning with EMT, even with a small run.

Sometimes, trying to communicate what I'm doing, and trying to figure out on my own how long something is going to take (and what to do next) can be trying. I imagine sometimes it sounds like I don't know what I'm doing, because when asked I tend to deliver a blank stare. :D

Peter D said:
George, why is all that piped? Are you not allowed to use MC cable?
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Actually, I heard it is somewhat prohibited in the plans. I didn't see it myself, but I imagine it's for the reasons Marc mentioned. :)
 
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peter d said:
George, why is all that piped? Are you not allowed to use MC cable?
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Peter, besides the issues with plane Jane MC and 517.13(A), 517.30(C)(3) will also come into play.

George, as far as proper application of a particular fire caulk, it must be done following a UL assembly, it appears as though you may be using a Hilti product and if so you can find an approved method on their website, UL's web site, or the UL orange books which is my preferred way.

Roger
 
Hospital005.jpg


Hmmmm... Somebody could use a "spacing comb". Get some plywood and cut a few notches like a big comb in say a 18"X6" piece, with equal spacing for laying out racks. Make life easier, and this rack look much better.
 
georgestolz said:
Can you elaborate? I try to fill in as best I can - I just trowel off the excess around the exterior of the hole to finish it up a bit.
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Also, if you are using a product, such as Hilti, or others, they will look at the prints and specify which product to use in which location. I am surprised the hospital or the Architect did not have this done. Just filling holes with product will not necessarily make it work when there is an actual fire.
 
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