Chances are you have encountered a wiring mass—or mess—somewhere along the road when installing voice/data/video or information transport systems. Year after year of adding, changing and rewiring may have left the plenum with little room for additional wiring and cabling.
Whether you have to negotiate miles of abandoned cable or want to install the best wire for the application and for future growth, wire and cable management is critical.
The environment takes precedence, too. Cabling is more likely to be manufactured with materials and processes that have less effect on the environment and can be recycled.
Manufacturers continue to do their part. Some have cable-management services and others are developing new information transport systems that bundle products more efficiently, take up less space, carry a “limited combustible” rating and are less likely to fuel a fire.
Still other companies in the industry are offering turnkey services to assist in tagging cable for removal, physically pulling it out and even disposing of it.
A hidden hazard
The industry is now recognizing abandoned cable is a hidden hazard, although those in information technology or voice/data/video probably made this discovery long ago. But the truth is that in addition to creating management, structural and air-flow problems, excess cable adds unnecessary fuel load in concealed building spaces.
Over the years, many types of cable made from a variety of materials have been installed in the concealed spaces of commercial and public buildings. Some of these materials were engineered to resist high heat, flame-spread and smoke-generation, while others were not. Abandoned cables may generate large amounts of smoke, making a fire extremely difficult to find and fight.
Removal of abandoned cable was required by the NFPA (National Fire Protection Association) 70, and the National Electric Code (NEC) 2002. Many local jurisdictions have adopted into law the provisions of the 2002 NEC that require the removal of abandoned cable.
What exactly is abandoned cable? In general, abandoned cable is no longer used for voice and data communications and other low-voltage signaling circuits in buildings. Specifically, the 2002 NEC Article 800 Communications Circuits defines abandoned cable as “Installed communications cable that is not terminated at both ends at a connector or other equipment and not identified for future use with a tag.”
Most end-users initiate removal projects when new cabling systems are added or during renovation.
“The change is effective as soon as the local authority having jurisdiction (AHJ) adopts either the 2002 or 2005 Code,” said Mark Earley, NFPA’s assistant vice president and chief electrical engineer and secretary of the NEC, Quincy, Mass. “Not only is the change relevant to fire concerns, but it also is designed to mitigate weight problems. In addition, for plenum spaces to work properly there needs to be airflow.”
All accessible cable not tagged for future use is part of the requirement, said Pat Lindner, DuPont Communications Cabling Solutions’ global business manager, Wilmington, Del. The requirement is based on NFPA’s concern over the uncontrolled build-up of combustible cables in buildings, Lindner said.
In May 2005, DuPont launched the Abandoned Cable Services business to aid companies in compliance with building safety codes and standards. DuPont, he said, conducts audits and has established a Preferred Contractor Network for referrals to handle removal of abandoned cable.
“We’re looking for local leaders in large metropolitan areas with a proven track record in cable and network design and installation,” Lindner said.
Call 866.383.5623 for more information about the DuPont Abandoned Cable Service.
As always, the first rule of thumb in any type of installation—burglar alarms, fire systems, network cabling and connectivity—is to check with the AHJ in the location where the work will be performed.
While most jurisdictions follow the NEC and require the removal of abandoned cable, the specific requirements for the building’s jurisdiction must be investigated by the contractor.
Cable management has become increasingly important in the last several years, not only because of NEC changes and regulations regarding abandoned cabling, but also because of an increased awareness of the performance of an information transport system as it relates to the installation, according to Robert Baxter, director, DataCom Marketing, Hubbell Premise Wiring, Hubbell Corp., Stonington, Conn. Baxter said a compromise in cabling, such as a kink or added weight, could easily cut signal strength in half.
“Cables today are designed so precisely and efficiently that any change to the geometry of the cable can affect performance and result in lost packets of data,” he said.
In addition, larger unshielded twisted pair (UTP) networks preparing for 10-gigabit Ethernet are contained in a much larger diameter cabling, which ultimately affects how much space is needed and used, said Glenn Kierstead, senior product manager of Copper Systems, Hubbell Premise Wiring.
“It’s critical when planning pathways to develop the space through active cable management and planning,” Kierstead said.
Hubbell recently developed a combination software/hardware technology to administer and trace cable in a building—from installation to final removal and disposal.
The Hubbell One system centers on one UTP highway or information transport system that can be used for Ethernet, audio, video, security and building automation. UTP is the most cost-effective media available, terminates quickly and allows installers to follow standard practices, Kierstead added.
H.H. Robertson Floor Systems, a division of Centria, based in Ambridge, Pa., supplied their wire-management system for a $57 million, 440,000-square-foot addition and renovation to the existing Allen County Public Library in Fort Wayne, Ind. The project is expected to be completed by fall 2006 and will use the company’s Q-Floor/Taproute System as the structured deck for the concrete floor slabs, and later, as an in-floor wire raceway system—an alternative to plenum cabling.
John Michlovic, National Marketing and Technical Manager, H.H. Robertson Floor Systems, said the composite cellular unit provides cabling capacity and easy activation of preset outlet boxes. In addition, “it allows full shear-stud capacity for efficient composite beam design, which can reduce horizontal steel frame weight by up to 35 percent.”
Used on elevated steel framework, H.H. Robertson’s cellular-floor system encapsulates all wire and cabling in steel cells within the concrete slab.
“With fireproofing installed on the underside of the cellular deck, it becomes the safest location for plastic covered cables,” Michlovic said.
“The fire resistance of plastic cable is not currently addressed by code. Most plenum-rated cable will ignite in one or two minutes of flame exposure. Although fire retardance is covered in NFPA 90A, fire resistance is not,” Michlovic said.
“If abandoned cables are a fire hazard, and the codes and standards require their removal, what about new or active cables made from the same plastics? Plastic-covered cables become less fire retardant and less fire resistant as they age but no testing is required after they are installed. Cabling standards and codes address only the tip of the iceberg when it comes to life safety. Code-approved does not necessarily mean safe,” he said.
“Architects, specifiers and code writers have to work proactively to create and use safer cable delivery systems such as cells, ducts and conduit to assure an adequate level of safety for building occupants,” Michlovic added. EC
O’MARA is the president of DLO Communications in Park Ridge, Ill., specializing in low-voltage. She can be reached at 847.384.1916 or firstname.lastname@example.org.