Contractors who install outside plant (OSP) cable systems need special knowledge and experience to install fiber optics. How well are you prepared for OSP installs? Correct answers and explanations are
in red.

1. Once the cable route is determined, the contractor must next determine ________ before any work can begin.
A. What kind of cable is needed
B. How much cable is needed
C. What kinds of equipment are needed
D. What permits are needed

Before you start choosing cables or equipment, you need to determine what permits will be required to bury the cable along the chosen route.

2. OSP buried fiber optic cables can be installed ________.
A. Pulled in conduit
B. Buried in innerduct
C. Direct buried with no conduit or ducting
D. Any of the above

All of these methods can be used when the proper cable is chosen and the installation location is appropriate.

3. Typically, cables are installed ________ to reduce the likelihood of being accidentally dug up and damaged.
A. 1–2 feet deep (0.5 meters)
B. 3–4 feet deep (1–1.2 meters)
C. Below the water line
D. Below the rocks

Generally cables are installed about 3-4 feet below ground, although it may be deeper in softer soil or closer to the surface in urban or suburban areas.

4. Direct buried cables use ________ for protection from crushing loads and rodent penetration.
A. Armor
B. Double jackets
C. Kevlar strength members
D. Concrete poured over the cable

Armor makes the cable stiffer to resist crush loading and hard for rodents to chew through the cable jacket.

5. Cables installed in conduit generally are inside innerduct or duct liner for easier pulling and protection.

Larger conduits usually have several cables so duct liners or innerduct keeps the cables separated and makes pulling easier.

6. Longer cable runs in conduit should use ________ when pulling tension is expected to be a problem.
A. High-powered pulling winches
B. Cable lubricants
C. Stronger cables
D. Smaller cables

Use of proper cable lubricants greatly reduces pulling tension.

7. Direct buried cables can be installed by ________.
A. Laying in trenches
B. Plowing the cable in
C. Directional boring
D. Laying in grooves sawed in roads or sidewalks
E. Any of the above

All of these methods are used to direct-bury fiber optic cable, depending on the location.

8. Direct buried cables can be plowed in instead of installed in trenches if the ground is soft and relatively rock-free.

Plowing-in cable works best in soft earth which has few rocks.

9. Cables with metallic armor must always be ________ for safety.
A. Taped to prevent cuts
B. Grounded and bonded
C. Stripped back at least 6 feet (2 meters)
D. Pulled with metallic pull ropes

Every metallic component of an OSP cable must be grounded and bonded. Splice closures have provision for grounding too.

10. According to the National Electrical Code, outside plant cables can only be brought ________ into a building before connection to fire-rated premises cables, unless they run inside conduit.
A. 5 feet (2 meters)
B. 15 feet (5 meters)
C. 50 feet (16 meters)
D. It depends on the diameter of the cable

Unless the cable is rated for flame retardance or run in metallic conduit, it can only go into a building 50 feet.

HAYES is a VDV writer and educator and the president of The Fiber Optic Association. Find him at