FLORIDA UNDERGROUND UTILITY
CONTRACTOR FINAL EXAM
QUESTIONS AND CORRECT ANSWERS
LATEST UPDATE
1. According to OSHA 1926 Subpart P, at what depth is a protective system required in a
trench, unless the excavation is made entirely in stable rock?
A. 3 feet
B. 4 feet
C. 5 feet
D. 6 feet
Answer: C
Conceptual Explanation: OSHA requires protective systems for trenches 5 feet deep or
greater, unless the excavation is in stable rock. Even at shallower depths, a competent
person may require protection if hazardous conditions exist.
2. In Florida, what is the minimum horizontal separation required between a new potable
water main and an existing or proposed sanitary sewer?
A. 10 feet
B. 6 feet
,C. 3 feet
D. 15 feet
Answer: A
Conceptual Explanation: Florida Administrative Code (FAC) 62-555 requires a minimum
horizontal separation of 10 feet between potable water mains and sanitary sewers to
prevent cross-contamination.
3. When installing a gravity sewer line, what is the minimum slope for an 8-inch diameter
pipe to maintain a scour velocity of 2 feet per second?
A. 0.28%
B. 0.33%
C. 0.40%
D. 0.50%
Answer: C
Conceptual Explanation: For an 8-inch pipe, a slope of 0.40% is the industry standard to
maintain the minimum scour velocity of 2 fps when flowing full or half-full.
4. Which soil type, as defined by OSHA, has an unconfined compressive strength of 0.5 tons
per square foot (tsf) or less?
A. Type A
B. Type B
, C. Type C
D. Stable Rock
Answer: C
Conceptual Explanation: Type C soil is the least stable, with an unconfined compressive
strength of 0.5 tsf or less, including granular soils and submerged soil.
5. What is the required test pressure for a hydrostatic leakage test on a new ductile iron
water main, according to AWWA C600 standards?
A. 100 psi or 1.25 times working pressure
B. 150 psi or 1.5 times the working pressure at the highest point
C. 200 psi for 4 hours
D. 50 psi above working pressure
Answer: B
Conceptual Explanation: AWWA C600 specifies that the test pressure should be at least
1.5 times the working pressure at the point of test, typically 150 psi minimum.
6. For a trench 4 feet or deeper, a ladder or other means of egress must be located so as not
to require more than how many feet of lateral travel?
A. 10 feet
B. 75 feet
C. 50 feet
CONTRACTOR FINAL EXAM
QUESTIONS AND CORRECT ANSWERS
LATEST UPDATE
1. According to OSHA 1926 Subpart P, at what depth is a protective system required in a
trench, unless the excavation is made entirely in stable rock?
A. 3 feet
B. 4 feet
C. 5 feet
D. 6 feet
Answer: C
Conceptual Explanation: OSHA requires protective systems for trenches 5 feet deep or
greater, unless the excavation is in stable rock. Even at shallower depths, a competent
person may require protection if hazardous conditions exist.
2. In Florida, what is the minimum horizontal separation required between a new potable
water main and an existing or proposed sanitary sewer?
A. 10 feet
B. 6 feet
,C. 3 feet
D. 15 feet
Answer: A
Conceptual Explanation: Florida Administrative Code (FAC) 62-555 requires a minimum
horizontal separation of 10 feet between potable water mains and sanitary sewers to
prevent cross-contamination.
3. When installing a gravity sewer line, what is the minimum slope for an 8-inch diameter
pipe to maintain a scour velocity of 2 feet per second?
A. 0.28%
B. 0.33%
C. 0.40%
D. 0.50%
Answer: C
Conceptual Explanation: For an 8-inch pipe, a slope of 0.40% is the industry standard to
maintain the minimum scour velocity of 2 fps when flowing full or half-full.
4. Which soil type, as defined by OSHA, has an unconfined compressive strength of 0.5 tons
per square foot (tsf) or less?
A. Type A
B. Type B
, C. Type C
D. Stable Rock
Answer: C
Conceptual Explanation: Type C soil is the least stable, with an unconfined compressive
strength of 0.5 tsf or less, including granular soils and submerged soil.
5. What is the required test pressure for a hydrostatic leakage test on a new ductile iron
water main, according to AWWA C600 standards?
A. 100 psi or 1.25 times working pressure
B. 150 psi or 1.5 times the working pressure at the highest point
C. 200 psi for 4 hours
D. 50 psi above working pressure
Answer: B
Conceptual Explanation: AWWA C600 specifies that the test pressure should be at least
1.5 times the working pressure at the point of test, typically 150 psi minimum.
6. For a trench 4 feet or deeper, a ladder or other means of egress must be located so as not
to require more than how many feet of lateral travel?
A. 10 feet
B. 75 feet
C. 50 feet
