COLORADO UNDERGROUND UTILITIES LOCATOR
CERTIFICATION EXAM QUESTIONS AND CORRECT
ANSWERS (VERIFIED ANSWERS) Q&A 2026
|INSTANT DOWNLOAD PDF
1. What is the primary purpose of underground utility
locating?
A. To increase excavation speed
B. To prevent damage to underground utilities
C. To replace engineering surveys
D. To reduce construction costs
Rationale: Utility locating ensures safety and prevents
accidental strikes to underground infrastructure.
Correct Answer: B
2. Before excavation begins, what must be done first?
A. Soil testing
B. Utility marking
C. Equipment mobilization
D. Backfilling
Rationale: Locating and marking utilities is required before any
digging begins.
Correct Answer: B
,3. Which system is commonly used to request utility locates in
Colorado?
A. OSHA Hotline
B. 811 Call Before You Dig
C. FEMA Alert System
D. EPA Locate Network
Rationale: 811 is the national “Call Before You Dig” system.
Correct Answer: B
4. What does a red utility marking typically indicate?
A. Water lines
B. Gas lines
C. Electric power lines
D. Sewer lines
Rationale: Red is universally used for electrical power systems.
Correct Answer: C
5. Which color represents potable water lines?
A. Blue
B. Yellow
C. Green
D. Orange
,Rationale: Blue markings indicate potable water systems.
Correct Answer: A
6. What is the typical tolerance zone around marked utilities?
A. 6 inches
B. 12–18 inches
C. 24–36 inches
D. 5 feet
Rationale: The tolerance zone varies, commonly 18–24 inches
depending on state rules.
Correct Answer: C
7. What tool is commonly used for electromagnetic utility
locating?
A. Hydrovac truck
B. EM locator receiver and transmitter
C. Ground pen
D. Backhoe
Rationale: EM locators detect signals on conductive utilities.
Correct Answer: B
8. What is a “tracer wire” used for?
, A. Measuring depth
B. Identifying non-metallic utilities
C. Increasing pipe strength
D. Detecting soil moisture
Rationale: Tracer wires help locate plastic pipes.
Correct Answer: B
9. Which color indicates natural gas lines?
A. Red
B. Yellow
C. Blue
D. Green
Rationale: Yellow is the standard for gas pipelines.
Correct Answer: B
10. What does white marking on the ground indicate?
A. Existing utilities
B. Proposed excavation area
C. Electric hazards
D. Sewer systems
Rationale: White is used to show proposed dig sites.
Correct Answer: B
CERTIFICATION EXAM QUESTIONS AND CORRECT
ANSWERS (VERIFIED ANSWERS) Q&A 2026
|INSTANT DOWNLOAD PDF
1. What is the primary purpose of underground utility
locating?
A. To increase excavation speed
B. To prevent damage to underground utilities
C. To replace engineering surveys
D. To reduce construction costs
Rationale: Utility locating ensures safety and prevents
accidental strikes to underground infrastructure.
Correct Answer: B
2. Before excavation begins, what must be done first?
A. Soil testing
B. Utility marking
C. Equipment mobilization
D. Backfilling
Rationale: Locating and marking utilities is required before any
digging begins.
Correct Answer: B
,3. Which system is commonly used to request utility locates in
Colorado?
A. OSHA Hotline
B. 811 Call Before You Dig
C. FEMA Alert System
D. EPA Locate Network
Rationale: 811 is the national “Call Before You Dig” system.
Correct Answer: B
4. What does a red utility marking typically indicate?
A. Water lines
B. Gas lines
C. Electric power lines
D. Sewer lines
Rationale: Red is universally used for electrical power systems.
Correct Answer: C
5. Which color represents potable water lines?
A. Blue
B. Yellow
C. Green
D. Orange
,Rationale: Blue markings indicate potable water systems.
Correct Answer: A
6. What is the typical tolerance zone around marked utilities?
A. 6 inches
B. 12–18 inches
C. 24–36 inches
D. 5 feet
Rationale: The tolerance zone varies, commonly 18–24 inches
depending on state rules.
Correct Answer: C
7. What tool is commonly used for electromagnetic utility
locating?
A. Hydrovac truck
B. EM locator receiver and transmitter
C. Ground pen
D. Backhoe
Rationale: EM locators detect signals on conductive utilities.
Correct Answer: B
8. What is a “tracer wire” used for?
, A. Measuring depth
B. Identifying non-metallic utilities
C. Increasing pipe strength
D. Detecting soil moisture
Rationale: Tracer wires help locate plastic pipes.
Correct Answer: B
9. Which color indicates natural gas lines?
A. Red
B. Yellow
C. Blue
D. Green
Rationale: Yellow is the standard for gas pipelines.
Correct Answer: B
10. What does white marking on the ground indicate?
A. Existing utilities
B. Proposed excavation area
C. Electric hazards
D. Sewer systems
Rationale: White is used to show proposed dig sites.
Correct Answer: B
