I’ve written monthly columns for ELECTRICAL CONTRACTOR for more than 20 years, many of which cover proper installation techniques for fiber optics. Articles also cover problems that come from poor installations. However, one topic I have rarely discussed in these pages is inspection of fiber optic cable plant installations.

Why haven’t I written about this recently? Because they are not generally required, and practically nobody ever does an inspection on a new fiber optic network.

Electrical installations are always inspected, of course, for safety reasons. But fiber optics and low-voltage copper communications cabling are considered intrinsically safe, and building and electrical codes rarely cover anything other than the flammability of cable jackets or the grounding of armored cables. Therefore, these plants are typically not inspected.

Customers are generally given documentation that covers the layout of the network and test results offered as proof it was installed properly. For fiber optic networks, that means the results of insertion loss attenuation tests and perhaps optical time-domain reflectometer tests.

A unique standard

About 20 years ago, the Fiber Optic Association (FOA) worked with NECA/NEIS to produce the ANSI/NECA/FOA 301 installation standard for fiber optics. NECA’s current Executive Director of Codes and Standards Michael Johnston described it well as a document to define how to “install fiber optics in a neat and workmanlike manner.” We’re currently working on the fourth revision of this document. It is unique in that other standards cover components or networks, but not installation.

NECA/FOA 301 was created as a document that could be used in RFQs and contracts to define workmanship for a fiber optic network. It could also be used as a reference document for inspection.

Unless workmanship is poor enough to cause bad test results, it’s not generally addressed, and usually only then by the installer to ensure it meets contract requirements. As a result, some installations exhibit really poor workmanship.

The most obvious workmanship issues are with aerial installations where the cables are hanging for all to see. We’ve seen cables that were improperly lashed to messenger wires, service loops of cables hanging off poles or messengers that contain hundreds of meters of cables, splice closures dangling from cables and crews overlashing another cable on a giant bundle of cables. Did they consider if the messenger was designed to support the weight of all those cables?

For underground cables, the problems begin with construction, where damage to other buried utilities is common. Some damage such as breaking a gas or water line is obvious, but there are others like puncturing drains or sewers while directional boring that are invisible. We saw photos of fiber installed in a city park that was not buried at all. It was discovered when it was cut by a landscaper mowing the grass.

Pulling cables into conduit is another problem. Fiber optic cables have limits on pulling tension and bend diameter that may cause immediate damage or long-term reliability issues. Splice closures are supposed to be sealed to prevent moisture damage, but poor quality components or sloppy workmanship may cause leaks. I’ve also seen fibers fail in splice closures because a fiber was pinched and broken when the splice tray cover was installed.

For premises cabling, the internet is full of pictures of telecom rooms with racks covered with deep layers of tangled cables. Not many people get to look above the ceiling or below the floor, but the conditions there are not pretty, either.

It’s easy to say this is just a training problem—which it is, of course. Well-trained techs who take pride in their work don’t make mistakes like these. But I know that many techs are not properly trained, if at all. Some are being pushed to work faster, which makes mistakes more likely. I know some techs are working on new components they have not been trained on or just watched a video to learn how to install.

We could also say this is a supervision problem. Supervisors should know their techs’ abilities and oversee their work to ensure proper workmanship.

Ultimately, it becomes the customer’s problem. They should inspect the installed cable plant themselves to ensure they get what they paid for. Unfortunately, many customers do not have the knowledge to judge the installation quality. I wonder if the lack of inspection isn’t a big part of the problem. 

Note: For a look at some installation problems that would never pass inspection, read this month’s online column, “Would This Workmanship Pass Inspections of Fiber Optic Projects?” on ECmag.com.

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