Ladder height? Ceiling clearance?

[Anonymous user]

Are there any requirements for the height of a cable ladder from the floor when spanning a walkway? Has anyone found the height of the ladder from the floor to be an issue? Next, are there any requirements for the clearance between the roofs, ladders, partitions, and troughs on the tops of the rack enclosures and the ceiling and ceiling fixtures such as room lighting? This is in California, USA.

I'm looking at installing a cable ladder (a 6" cable ladder for data cables in this case) in our raised floor data center. Since roof-top ladders (or cable partitions) do not have to be used when a raised floor is available, there may be more issues with using a ladder.

The new 42U SX AR3100 enclosures have been installed by our outside contractor, meaning the enclosures have been bolted through the raised floor to the sub floor with the leveling feet in position and with the enclosures bayed together. I have APC scheduled to install the ladder, data cable partitions, and accessories under Assembly Services. As installed the enclosures are about 78 1/2 inches tall (1994 mm). The first ladder will connect two rows of enclosures, spanning the "cold" aisle.

From the documentation it looks it looks like the data cable ladder when run between the data cable partitions with pass-throughs sits just above the roof of the enclosure or right on top of it. (The ladder parts are still packed in the boxes for APC to unpack.) In a nutshell, it looks like a person over 6 feet 6 inches tall (198 cm) could bump one's head on the ladder. Has anyone run into issues over this? Are there safety regulations (US OSHA / Cal OSHA) regarding this?

I looked into options for raising the height of the ladder.

I have the Cable Ladder Attachment Kit, NetShelter SX (AR8168BLK) that I was planning to use for a different ladder. It looks like attaching to these instead of to the data cable partitions gets the ladder 1/2" higher maybe. Next, it looks like if you attach the ladder to a power cable trough instead and also use brackets such as the Cable Ladder Attachment Kit, 750mmWide, Power Cable Troughs (AR8176BLK) which I don't have that this raises the ladder still higher. (This ladder would be run between a 750mm and a 600mm wide enclosure. I also have the AR8177BLK brackets included in the order.)

Is there any way that the APC installers have to raise the ladder up a couple inches if this is necessary?

If I use the SX-to-VX roof match kits it looks like the ladder would be 82 1/2 inches (2095 mm) above the floor by my estimate looking at the specs. This looks like a height that may be more acceptable since the "7 foot" doors into the data center actually have this same clearance of 82 1/2 inches.

I have one 750mm wide roof match that was going to be used for another ladder (between an SX and a VX) that could be installed later. I would need a 600mm wide roof match. These are fairly expensive and slow to order.

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Other part of the question. Although the shorter height of the SX 42U as compared to the VX enclosures lowers the ladder height, it helps with the overhead clearance. In this data center the room lights are long units suspended from the drop ceiling with the bottoms of the lights about 8 feet above the floor. (The lights are not panels flush to the drop ceiling.) The sprinklers extend slightly from the drop ceiling, ending well above the lights. I was going to maintain a 1 foot clearance from the top of the data cable partitions to the lights. This is easily met when using the data cable partitions with the 42U SX enclosures. Does anyone know if there are regulations concerning this clearance? I have three 42U VX enclosures currently with no partitions that I was going to do without partitions on top of because on these taller enclosures the data cable partitions would be less than 1 foot from the lights. (The two SX enclosures where I was thinking of using the roof matches to raise the ladder height happen to be in a location that is not directly under the lights so the 1 foot clearance could still be met.) I would like to put data cable partitions on the existing VXs as well if possible.

I got the 1 foot clearance from training on Data Center University where a 1 foot clearance from the ceiling was required in a data center with lights flush to the drop ceiling and with sprinklers on the drop ceiling. I took the 1 foot and applied it to the bottom of the lowered lights.

[cmarler_apc]

Great questions, and you are right about the one foot clearance.
Being tall, I share your concern, even though you don't have too many 6'6" guys in the data center, it does feel claustrophopic with low cable ladders. Hang em high, I say.

If you can go up to power trough height and still maintain clearance, go ahead and use the SX to VX rack height adapters everywhere.
Use as many as you need to obtain a uniform height of the power troughs on every rack. Then you will be able to span the data cable ladder from the power troughs across the cold aisles wherever you need, at the highest point across the aisle.
...and another tip, if you hate looking up through the cable ladder at cables, put fish paper liner on the cable trays before you lay out cables. The panduit guys did that in here and it looks great.

...and although you can normally get closer than a foot to the light fixtures without being in violation of any codes, the maintenance guys will grumble replacing bulbs, but sprinkler heads are a different story. You might need 18" in some jurisdictions or buildings. Check local building codes for all this stuff. I've seen strange stuff just within local munipalities in California, not necessarily on fire suppression discharge cleareance, but in electrical code adoption. The building guys will best be able to advise you on any regulatory compliance.

[Anonymous user]

Thanks. I have a few power troughs included in the solution and will have the installer use these for the ladder. That should get the ladder high enough?about the same as the room door clearance?without using the roof match kit, which I'll save for a short ladder in a different location between an SX and VX in a "between aisles" configuration. Elsewhere the power troughs would end up coming within the 1 foot of the lights even without the roof match and the data partitions with the roof match would be within the 1 foot.

Since the ladder will be running between a 750mm and a 600mm enclosure I hope the slots in the troughs will still line up.

[cmarler_apc]

I'd agree...if you are above the level of the door, you should be good... and...the slots are centered in the power troughs and partitions so your suspicion is correct spanning from the 600mm to the 750mm rack with the ladder. Either use a cable ladder attachment kit AR8168BLK or just use the cable ladder attachment kit, 750mm Wide AR8177BLK on the power trough.
Good luck!

[Anonymous user]

The cable ladder is installed now--83 1/2 inches off the floor when run between two power troughs on top of the 42U SX enclosures (without the roof matches and using the AR8176BLK brackets since the different widths 600mm and 750mm enclosures do not line up). This height should be high enough since it is the same as the clearance under the 7 foot doors into the room.
Thanks.

[Anonymous user · Accepted solution]

Are there any requirements for the height of a cable ladder from the floor when spanning a walkway? Has anyone found the height of the ladder from the floor to be an issue? Next, are there any requirements for the clearance between the roofs, ladders, partitions, and troughs on the tops of the rack enclosures and the ceiling and ceiling fixtures such as room lighting? This is in California, USA.

I'm looking at installing a cable ladder (a 6" cable ladder for data cables in this case) in our raised floor data center. Since roof-top ladders (or cable partitions) do not have to be used when a raised floor is available, there may be more issues with using a ladder.

The new 42U SX AR3100 enclosures have been installed by our outside contractor, meaning the enclosures have been bolted through the raised floor to the sub floor with the leveling feet in position and with the enclosures bayed together. I have APC scheduled to install the ladder, data cable partitions, and accessories under Assembly Services. As installed the enclosures are about 78 1/2 inches tall (1994 mm). The first ladder will connect two rows of enclosures, spanning the "cold" aisle.

From the documentation it looks it looks like the data cable ladder when run between the data cable partitions with pass-throughs sits just above the roof of the enclosure or right on top of it. (The ladder parts are still packed in the boxes for APC to unpack.) In a nutshell, it looks like a person over 6 feet 6 inches tall (198 cm) could bump one's head on the ladder. Has anyone run into issues over this? Are there safety regulations (US OSHA / Cal OSHA) regarding this?

I looked into options for raising the height of the ladder.

I have the Cable Ladder Attachment Kit, NetShelter SX (AR8168BLK) that I was planning to use for a different ladder. It looks like attaching to these instead of to the data cable partitions gets the ladder 1/2" higher maybe. Next, it looks like if you attach the ladder to a power cable trough instead and also use brackets such as the Cable Ladder Attachment Kit, 750mmWide, Power Cable Troughs (AR8176BLK) which I don't have that this raises the ladder still higher. (This ladder would be run between a 750mm and a 600mm wide enclosure. I also have the AR8177BLK brackets included in the order.)

Is there any way that the APC installers have to raise the ladder up a couple inches if this is necessary?

If I use the SX-to-VX roof match kits it looks like the ladder would be 82 1/2 inches (2095 mm) above the floor by my estimate looking at the specs. This looks like a height that may be more acceptable since the "7 foot" doors into the data center actually have this same clearance of 82 1/2 inches.

I have one 750mm wide roof match that was going to be used for another ladder (between an SX and a VX) that could be installed later. I would need a 600mm wide roof match. These are fairly expensive and slow to order.

----------

Other part of the question. Although the shorter height of the SX 42U as compared to the VX enclosures lowers the ladder height, it helps with the overhead clearance. In this data center the room lights are long units suspended from the drop ceiling with the bottoms of the lights about 8 feet above the floor. (The lights are not panels flush to the drop ceiling.) The sprinklers extend slightly from the drop ceiling, ending well above the lights. I was going to maintain a 1 foot clearance from the top of the data cable partitions to the lights. This is easily met when using the data cable partitions with the 42U SX enclosures. Does anyone know if there are regulations concerning this clearance? I have three 42U VX enclosures currently with no partitions that I was going to do without partitions on top of because on these taller enclosures the data cable partitions would be less than 1 foot from the lights. (The two SX enclosures where I was thinking of using the roof matches to raise the ladder height happen to be in a location that is not directly under the lights so the 1 foot clearance could still be met.) I would like to put data cable partitions on the existing VXs as well if possible.

I got the 1 foot clearance from training on Data Center University where a 1 foot clearance from the ceiling was required in a data center with lights flush to the drop ceiling and with sprinklers on the drop ceiling. I took the 1 foot and applied it to the bottom of the lowered lights.