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Engineering & Design: Customer-Owned Outside Plant Design: Who Needs It?

Customer-Owned Outside Plant (CO-OSP) design has been garnering much attention of late. But what is it really? And who is it for?

December 1, 2001  

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Customer-Owned Outside Plant (CO-OSP) design is an emerging specialty in the cabling industry. Driven by deregulation, the CO-OSP field has garnered enough attention lately to warrant a new professional designation. Called the RCDD/OSP Specialty, the designation was recently conferred by BICSI.

But what is CO-OSP design — and who needs it?

As communications designers involve themselves more and more in providing a total package for their clients, they are finding that outside plant design is in higher demand. Structured cabling networks are expanding into metropolitan area networks (MANs) and other larger serving areas, creating opportunities to apply outside design skills.

Communications designers who would normally have been concentrated within the confines of a building are working outside these lines to provide fully integrated designs for their clients. Careful understanding of the nuances of outside plant design is critical in ensuring the success of these growing projects.


There are many specific, complex considerations that confront designers with regard to outside plant design. Typically, these considerations are all part of the pathway choices involved with the design of aerial, buried and underground structured cabling. Many of the common issues include pathway locations, right-of-way needs, structured pathway design, depth and clearance requirements, safety, project management and cabling decisions.

A unique aspect of CO-OSP occurs when designs require these projects to be independent networks that co-exist within public right-of-way with other providers. This makes for a most challenging environment, and designers must be creative and apply all of their skills to work through these obstacles.

Because the customer is involved in the decision process, the designer must sometimes adhere to the customer’s particular preferences. The designer will make recommendations on the most suitable applications, but the final needs of the customer may ultimately override these choices. Understanding the complexities in these decisions is essential for creating a detailed, structurally sound plan that delivers the desired results to the client.


We have all heard real-estate people claim the “location, location, location” motto as their preferred choice, and it definitely applies to outside plant design.

The pathway location is the first decision that any designer will be required to make, and with pathways getting more and more congested, this decision is also becoming the most difficult. Many considerations go into selecting the pathway location and this will usually dictate the most suitable method of placement.

For example, as cost is often the client’s main concern, the desired pathway choice may be aerial on an existing pole line. However, the pole line may not be adequate to accommodate these additions and may require rebuilding. It then becomes more cost efficient to bury or place underground conduits. Perhaps burying is the desired pathway, but due to the heavy restoration costs involved, an aerial pathway will become the cost-effective choice. Carefully examining all of the considerations will help to determine whether the pathways will be aerial, buried or underground.

To underscore the importance of sound decision-making, remember that this decision is usually permanent and must survive the test of time. Designers must consider both the current and future ramifications of pathway location decisions.


There are many components that a designer must accommodate when applying a pathway design. Customers’ opinions and requirements dictate most decisions on costs, aesthetics and future requirements. However, designers must also follow governmental regulations, in addition to natural factors and physical and transmission restrictions. A designer’s responsibility and success depends on knowing the limitations and proper applications for all of these factors.

Aerial design brings with it some unique challenges, such as aesthetics, topography, clearances, obstacles, permits, other attachments, and of course, weather. Especially important to aerial design is accommodating loads imposed on pole lines and adhering to safety codes or other requirements when working around them.

Permits may also be required for buried design. Additionally, the cost, soil condition, depth, location, installation method and conduit maintenance hole needs must all be considered. One of the most often overlooked concerns is the location of other existing underground obstacles. Damage prevention and project feasibility require that any obstructions be defined in advance of proposing pathway choices.

When planning for underground design, one must pay close attention to future access and maintenance. Costs, possible future additions, aesthetics and protection are of equal concern. Experience has shown that a well-planned underground system can be one of the best pathway systems for communications systems — especially when expansion is expected.

To provide full connectivity for a client, it is often necessary to leave the customer’s property and connect to other buildings. In these cases, right-of-way, permitting, coordination and agreements for make-ready joint-use situations become additional challenges.

Often, these conditions must be researched outside the job site and are determined after the initial field surveys have been completed. The various owners, agencies and Authorities Having Jurisdiction (AHJ) should be consulted for final decisions. The designer must be able to provide the client with all of the options available while securing these mandatory requirements.


Because of the heavy and structurally-challenging equipment and materials involved in outside plant installations, designers must be fully informed about potentially life threatening issues. The safety of the construction personnel applying the designs must be a big part of a designer’s considerations when developing plans.

For example, when proposing outside plant installations around gas, electric and other hazardous utilities, the designer must be sure that there are no conflicts that may place the construction crew in harm’s way. In addition, when depths require trenching that must be shored or protected by other means, the designer must be sure that the design includes the materials and specifications to protect crews that will be involved.


For years, the outside plant design has always had the same customer — the telephone company. Now, the industry is recognizing that the customer can be anyone building a network or campus system.

Customer-Owned Outside Plant is just as the name implies — “owned”. And with ownership comes all of the responsibility for design, installation and maintenance. More and more organizations today are asking for consultants who are qualified in the understanding and planning of the issues inherent in the ownership agreement.

By paying attention to detail, taking the time to understand the complexities, and gaining a greater awareness of the RCDD/OSP Specialty, more and more cabling system designers will find that their expertise warrants both the professional designation offered and the accompanying client opportunities.CS

Joe Hite, RCDD/OSP, is Special Projects Engineer at CT Communications (, the 22nd largest telecommunications company in the U.S., based in North Carolina. Joe is also a member of the BICSI Committee for the Customer-Owned Outside Plant Design Manual. He can be reached at

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