I've been given the task of moving a small datacenter (3 Racks) into a new building where a server room was built with water sprinklers. The issue was raised and the contractor changed it to an FM200 system. I'm not sure who hired these guys or what the outcome will be b/c they have turned to me to find out how to seal the cable routes going into the ceiling (seems like they should know this?).

Essentially we have a cable ladder going from the racks to the wall and all the cables are bundled into 2 x 3 or 4 inch bundles passing through a ceiling tile.

The contractors idea was to form a 'collar' to wrap around each bundle with pvc piping and fill it with foam... I've seen this with indoor/outdoor conduits, such as those that might lead back to a demark.

Is this a good idea? It seems like any movement on the cables would cause gaps in the foam... or the foam might affect the cables' insulation... and it seems like itll be a huge pain to run cables in the future...

What is the right solution? Thanks in advance!

  • Our cable contractors typically use a red fire-proof putty when running conduit into our data centers. It looks and feels like clay although I'm not sure what they call it as I rely on them for that sort of thing. – Paul Ackerman Dec 14 '11 at 17:32
  • The technical term for that is a firestop. – Andrew Dec 14 '11 at 23:45

Honestly, you won't be able to create a 100% air-tight room. No point in trying to. Most fire-suppression systems are deliberately designed with a certain amount of escaping air. That being said... The guy selling DuPont products should be the one to consult on this. You're the customer, not the service provider.

  • As TCW says, the FM200 people should come in and run a leak-test on the room (basically, they pressurise it, then watch how the overpressure degrades over 10-30 minutes). They'll advise on how much more sealing is required, and if they're any good at all, they'll advise on how. You can cause more trouble than not if you use eg non-flame retardant materials in order to pressure seal! – MadHatter Dec 14 '11 at 17:26
  • @MadHatter - Hah I read that as "As Tasty Coma Wife says..." - took me a moment to realise you meant TheCompWiz ;) – Mark Henderson Dec 14 '11 at 21:36

having gone through this exercise before you are in for lots of fun. Even if they get it right by their standards, your local fire marshal may have a different opinion. My recommendation is to try to reduce the number of cables going into that room, and then run the cables through the approved conduit. You won't be running any more cables though that conduit when finished so its usually advisable to make this a 10g switch to 10g switch line rather than expecting to use the conduit.

  • +1 for "when it's built, it ain't changin'" – Driftpeasant Dec 14 '11 at 22:15

Your Answer

By clicking "Post Your Answer", you acknowledge that you have read our updated terms of service, privacy policy and cookie policy, and that your continued use of the website is subject to these policies.

Not the answer you're looking for? Browse other questions tagged or ask your own question.