As the 2011 National Electrical Code indicates, it’s not just riser-rated cables that can be used in riser spaces.
By Stanley Kaufman, Cablesafe Inc.
The National Electrical Code is published by the National Fire Protection Association with revisions on a three-year schedule. The 2011 NEC, which replaces the 2008 NEC, was released by NFPA in August 2010. There were many changes of interest to manufacturers, installers and users of communications cable and connectivity products.
This is the fourth article in a series of nine articles, sponsored by the Communications Cable and Connectivity Association, concerning those relevant changes in the NEC. The initial article was an introduction to the NEC, its scope and organization. The second article discussed the changes in types and installation rules for data/comm raceways and the third discussed the changes in the permitted applications of data/comm cables in air handling spaces.
This article deals with changes in the wiring rules for data/comm cables in riser applications. In addition to riser cables (CMR, OFNR, CL2R, etc.), plenum cables (CMP, OFNP, CL2P, etc.) are used in riser applications because plenum cables are permitted to substitute for riser cables. General-purpose cables (CM, OFN, CL2, etc.) are also permitted to be used in some riser applications, but the typical riser cable is either a riser-rated or plenum-rated cable.
This article deals with changes in the wiring rules for plenum, riser and general-purpose data/comm cables in riser applications.
- Types CL2P, CL2R and CL2, Class 2 Plenum, Riser and General-Purpose Cables
- Types CL3P, CL3R and CL3, Class 3 Plenum, Riser and General-Purpose Cables
- Types OFNP, OFNR and OFN, Nonconductive Optical Fiber Plenum, Riser and General-Purpose Cables
- Types OFCP, OFCR and OFC, Conductive Optical Fiber Plenum, Riser and General-Purpose Cables
- Types CMP, CMR, CM and CNG, Communications Plenum, Riser and General- Purpose Cables
- Types CATVP, CATVR and CATV, Cable TV Plenum, Riser and General-Purpose Cables
- Types FPLP, FPLR and FPL, Power-Limited Fire Alarm Plenum, Riser and General-Purpose Cables
Listing requirements for data-communications riser cables
All data/comm riser cables are listed as “suitable for use in a vertical run in a shaft or from floor to floor” and also listed as “having fire-resistant characteristics capable of preventing the carrying of fire from floor to floor.” The listing requirements are followed by an informational note referring to ANSI/UL 1666-2002, Test for Flame Propagation Height of Electrical and Optical-Fiber Cable Installed Vertically in Shafts. The test uses a substantial fire source to determine whether or not a cable will spread fire to the floor above.
Data-communications cables in riser applications
Consistent with their listings in the 2008 and 2011 NEC, all data/comm riser cables are permitted to be used in all riser applications. In addition, each type of data/comm plenum cable, is permitted to substitute for its riser cable because the severity of testing requirements for plenum cables exceeds the requirements for testing riser cables.
In the 2008 and 2011 NEC, there are three situations in which all data/comm cables (plenum, riser and general-purpose) are permitted to be installed:
- In fireproof shafts with firestops at each floor
- In one- and two-family dwellings
- In metal raceway
Other than in one- and two-family dwellings the 2008 NEC permits general-purpose data/comm cables (Types CL2, CL3, OFN, OFC, CM, CMG, CATV and FPL) to be used in vertical runs penetrating only one floor. However these general-purpose cables are not permitted to be installed in the same floor penetration as the floor penetration containing riser or plenum cables. The floor penetration containing riser or plenum cables was typically part of a riser system that extended to multiple floors, and the inclusion of general-purpose cables in the floor penetration could result in fire spread from floor to floor to floor.
In the 2011 NEC the applications of optical fiber and communications data/comm cables have been simplified. The provision for using Types OFN, OFC, CM, CMG and CATV general-purpose cables in vertical runs penetrating only one floor (in their own dedicated floor penetration) has been deleted. These applications now require riser cable (or plenum cable as a substitute for riser cable).
The applications of class 2, class 3 and power-limited fire alarm general-purpose cables remain the same in the 2011 NEC as in the 2008 NEC.
Section 725.154(G) permits general-purpose communications cables (Types CM and CMG) to substitute for general-purpose class 2 and class 3 cables (Types CL2 and CL3) but requires the substitute cables to be installed in accordance with the wiring rules for class 2 and class 3 cables. A similar rule in section 760.154(D) permits Types CM and CMG to substitute for Type FPL but requires the substitute cables to be installed in accordance with the wiring rules for fire alarm cables. Consequently, Types CM and CMG cables are not permitted to be used in riser applications penetrating only one floor when they are being used for a communications application (Article 800) but they are permitted to be used in riser applications penetrating only one floor when they are being used in a class 2, class 3 or power-limited fire alarm circuit.
A simple way to comply with these complicated code requirements is to use plenum or riser cables in all riser applications. A further simplification is to use communications cables in place of class 2 or class 3 cables; if you do so, it will not be necessary to determine if the circuit is a data circuit or a communications circuit.
The deadline for proposals for the 2014 NEC is November 4, 2011.
My next article will deal with cable routing assemblies.
Author’s disclaimer: This paper, provided by the Communication Cable and Connectivity Association (“CCCA”), is offered for general information and educational purposes. It is not offered, intended, nor should it be relied upon as legal advice. The paper does not set forth the views of any member or any other party, nor may it be taken as such. CCCA makes no warranty regarding the accuracy of the information provided in this paper, and expressly disclaims any implied warranties and any liability for use of the paper or reliance on views expressed in it. CCCA does not endorse, approve, or certify any information set forth in this paper, nor does it guarantee the accuracy, completeness, efficacy, timeliness, or correct sequencing of such information. Use of the paper and the views expressed in it is voluntary, and reliance on it should only be undertaken after an independent review of its accuracy, completeness, efficacy, and timeliness, and based on the individual facts and circumstances of a user.
Stanley Kaufman, Ph.D. is principal of CableSafe Inc. and a consultant to the Communications Cable and Connectivity Association (CCCA; www.cccassoc.org). He is a member of NEC Panel 12 (responsible for Article 645) and Panel 16 (responsible for optical fiber and communications cables).
CCCA elects officers, executive committee, pledges more vigilance
The Communications Cable and Connectivity Association (CCCA) recently held its annual meeting, at which it elected new officers. Kevin Ressler of TE Connectivity was elected chairman of the board; Randy Mortensen of Anixter was elected secretary; and Rob Wessels of CommScope was elected treasurer. They are joined by executive committee members Kevin St. Cyr of Berk-Tek and Gary Stanitis of Daikin America.
CCCA executive director Frank Peri said, “I’m looking forward to working with CCCA’s new officers and governing body, who are equally committed to preventing potentially hazardous, non-compliant cable from being imported, distributed and sold in the U.S. market. We still have a long way to go. Through our industry alerts and continuing work with UL, we are making progress.”
Ressler commented, “I want to congratulate outgoing officers and members of the executive committee for their valuable contributions, which guided CCCA’s growth and raised value to members and the structured cabling industry. My goal is to continue a tradition of growth by broadening our membership base and supporting CCCA initiatives that strengthen the quality and integrity of our industry.”
Also recently, the CCCA welcomed comCables and Panduit as members of the association. Upon becoming a member, Panduit’s Tom Kelly stated, “Panduit has been impressed with CCCA’s initiatives and activity to stem the importation of potentially hazardous, non-compliant cables into North America. We view CCCA as a strong industry association and excellent platform for Panduit, and other members, to address the proliferation of counterfeit products plaguing all levels of the structured cabling industry.”
-Patrick McLaughlin