Engineering Quality Bulletin
Engineering Quality Bulletin Number: 03-02
Origional Engineering Quality Bulletin Number: 04-02
To: All Engineering Suppliers / Planning & Design Engineering Representatives / Engineering & Installation Quality Auditors /AMC Representatives
Date: Thursday, April 11, 2003
From: Qwest Engineering Quality Assurance
Subject: Fiber Optic Cabling Support in the Central Office Environment.
Action Required:
YES: / Ö / NO:
Description of Bulletin:
The purpose of this document is to clarify Qwest’s policy on the proper fiber optic cable support requirements for central office environments within the 14-state region. Qwest-approved Optical Fiber Nonconductive Riser (OFNR) cables meet the requirements and objectives as documented in Telcordia’s GR-409-COREâ ensuring cable rack support qualifications.
Acknowledgements to Diana Unser for her contribution to this Bulletin. Inquiries can be directed to her at (303) 707-7559.
Qwest Engineering Quality Assurance
Don Noffsinger
303-707-7590
mailto:
Fiber Optic Cable Support in Central Office Environments
When engineering or installing a cable support system for all Qwest-approved OFNR-rated fiber optic cables, the following options are listed in the order of priority:
1ST CHOICE - All sizes of OFNR-rated Fiber Optic Cables
· Run on Qwest-approved, orange, solid stringer ladder-type cable rack equipped with kydex panning and brackets.
· 20" is the standard size for new 7' Floor-Supported systems unless specific office conditions, Qwest capacity decisions, or Qwest Standard Configuration documents dictate different size requirements. Fiber cable racks must be sized for ultimate, long-term capacities.
RESTRICTED - ADC FiberGuide (Yellow Duct)
· Used to extend existing arrangements to their logical conclusion only, no new 7' floor- supported areas.
· Used only for the support and protection of older OFN-type jumpers or patch cords, not for OFNR-type cables unless office conditions prevent the addition of fiber-only orange cable rack.
· Limited to singles / dual fiber cables. ADC FiberGuide does not maintain the minimum bend radius for any larger fiber cable sizes.
· 2"x 2" solid duct for horizontal runs is restricted to customer premises, CEV, CEC, and hut applications only.
· 2"x 2" multi-slotted vertical duct is placed on each fiber equipment frame upright to protect the fiber optic cables feeding to that frame / shelf. Using the approved 2"x 2" to serve more than one frame is prohibited.
· Split-flex tubing is approved to provide a transition from a 4"x 4" or 4"x 6"solid duct to a 2"x 2" multi-slotted vertical duct mounted on an equipment frame upright. Any other use is prohibited.
· 4"x 4" and 4"x 6" sizes are conditionally approved for existing lineup applications. 4"x 12" sizes are strictly limited to being locating above a FDF or NGF where a fiber-only cable rack cannot be installed and existing space will allow.
· Covers are required on all straight sections and fittings. Only Qwest-approved fittings shall be used in Qwest central office environments.
RESTRICTED – Lucent Technologies (Orange Duct)
· Extend existing lineup arrangements to logical conclusion only.
· No new lineups / arrangements.
· Convert to ADC FiberGuide (OFN fiber cables) or Qwest-approved orange fiber-only cable rack (OFNR fiber cables) where possible.
· Covers are required on all straight sections and fittings.
Additional Fiber Optic Cable Requirements
· Orange corner brackets are required on every horizontal 90-degree corner required to support the fiber cable. The OFNR fiber cables must be secured (Qwest Tech Pub 77350) to the corner bracket to maintain bend radius.
· Vertical OFNR fiber cables must be wrapped with fiber sheeting and tied to every vertical cable rack cross-strap.
· 45-degree fixed clips or inside/outside orange 90-degree cable rack fabrications will be used wherever possible for fiber cable rack changes in level or waterfalls in order to maintain the minimum fiber optic cable bend radius.
· Where possible, all quad and smaller fiber cables will be bundled together and loosely secured every 5'-6' along the entire horizontal fiber cable route.
· Fiber Optic Cable slack storage within dedicated, segregated fiber-only cable racks or fiber duct type protection systems is strictly prohibited. Looping / coiling fiber cables within any dedicated fiber support system is strictly prohibited.
· NO stenciling or labeling of Qwest-approved orange ladder cable rack, yellow ADC FiberGuide, nor Lucent orange duct is required.
· Use of yellow or orange duct / cable rack for any other purpose than supporting or routing fiber optic cables in a CO environment is strictly prohibited.
· Adherence to fiber cable pileup limits within approved fiber cable support systems (Qwest Tech Pub 77351) is mandatory.
· OSP outdoor rated fiber cable must be spliced and converted to indoor-rated fiber cable at an approved splice facility within 50-sheathed feet of entrance into the CO environment.
· Placing fiber duct systems and OFN-rated fiber cables through a floor or wall cable penetration is strictly prohibited.
· Fiber cable is secured (Qwest Tech Pub 77350) on all vertical transitions. Pans & brackets on cable rack waterfalls or changes in level are strictly prohibited.
Reference Documentation:
· Qwest Tech Pub 77351, Engineering Standards General Equipment Requirements, Module 1
· Qwest Tech Pub 77350, Telecommunications Equipment Installation Guidelines
· Qwest Standard Configuration Documents
· Qwest Common Systems Home Page
· Telcordia GR-409-COREâ, Generic Requirements for Premises Fiber Optic Cable
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