OSP OSP Conduit & Duct Systems 2 — Questions and Answers
Question 1: What does the term 'innerduct' refer to in an OSP conduit system?
- A smaller conduit installed inside a larger conduit to subdivide it for multiple cables (Correct answer)
- The inner wall coating of a standard conduit
- An underground vault used for cable storage
- A type of flexible conduit used at building entrances
Correct answer: A smaller conduit installed inside a larger conduit to subdivide it for multiple cables
Innerduct is a smaller subduct placed inside a larger host conduit to create multiple separate pathways, allowing different cables or providers to share a single conduit.
Question 2: Which manhole class designation according to AASHTO standards is typically specified for manholes installed under paved roadways that may carry heavy truck traffic?
- Class A (light duty)
- Class B (medium duty)
- Class C (heavy duty) (Correct answer)
- Class D (extra heavy duty)
Correct answer: Class C (heavy duty)
AASHTO Class C (heavy duty) manholes are specified for installations under paved roadways subject to heavy truck traffic, meeting H-20 or higher load ratings.
Question 3: In OSP design, what is a 'duct bank envelope'?
- A protective plastic sleeve around conduit
- The cross-sectional concrete encasement surrounding a group of conduits (Correct answer)
- A document listing all conduit sizes in a design
- An underground junction box
Correct answer: The cross-sectional concrete encasement surrounding a group of conduits
A duct bank envelope refers to the cross-sectional area of concrete or controlled low-strength material (CLSM) that encases and protects a group of conduits from mechanical damage and soil settlement.
Question 4: What is the standard color coding for HDPE conduit designated for fiber optic telecommunications in US outside plant applications?
- Red
- Blue
- Orange (Correct answer)
- Yellow
Correct answer: Orange
Orange is the standard color designation for telecommunications fiber optic conduit in US OSP applications, helping field crews identify the correct conduit type during installation and maintenance.
Question 5: What minimum vertical separation is required between a telecommunications duct bank and a high-voltage electric power duct bank when they must run parallel?
- 3 inches
- 6 inches
- 12 inches (Correct answer)
- 24 inches
Correct answer: 12 inches
Industry standards and the NEC generally require at least 12 inches of vertical separation between telecommunications and high-voltage electric power duct banks running in parallel to prevent electromagnetic interference and safety hazards.
Question 6: What does 'CLSM' stand for as used in duct bank construction?
- Cured Lateral Seal Mix
- Controlled Low-Strength Material (Correct answer)
- Conduit Locking Sleeve Method
- Compacted Layered Sand Medium
Correct answer: Controlled Low-Strength Material
CLSM stands for Controlled Low-Strength Material, a flowable fill mixture used to encapsulate duct banks because it flows around conduits completely and can be excavated later if needed.
OSP OSP Conduit & Duct Systems 2
What does the term 'innerduct' refer to in an OSP conduit system?