Securing MC Cable Under Office Raised Floor

[ed downey]

I have a situation where the AHJ is requiring that we support (or secure) MC cable under a raised access floor for an office building (open office scenario) at 4.5' intervals. This seems a little excessive for MC cable laying on a concrete floor. This project is under the 2002 NEC and we are using 300.22(C) for the installation of MC cable in an location used for environmental air.

Can someone please help me with a code reference for either having to support/secure the MC or not having to support the MC cable at 4.5' intervals.

Thanks,
-Ed

 

[iwire]

Re: Securing MC Cable Under Office Raised Floor

330.30 Securing and Supporting.
Type MC cable shall be supported and secured at intervals not exceeding 1.8 m (6 ft).

IMO the inspector is thinking of NM and AC cable support requirements.

 

[bphgravity]

Re: Securing MC Cable Under Office Raised Floor

YOu have to both support and secure cables. In many cases, this is done in one step. In your case, it appears you have supported the cable by laying it directly on the floor, however it does not appear the cable is secured.

By the way, MC is only required to be secured and suported at 6' intervals. See 330.30

 

[iwire]

Re: Securing MC Cable Under Office Raised Floor

How would it be possible to secure a cable every 6' without it being supported at the same time?

 

[ed downey]

Re: Securing MC Cable Under Office Raised Floor

The AHJ is stating that We would need to secure the MC cable to the legs of the raised access floor using plenum rated Tyraps. I cannot see anyway around this for MC Cable.

Thanks for your replies.

-Ed