AZ L-20 Demolition Contractor Exam
Questions And Correct Answers
(Verified Answers) Plus Rationale2026
Q&A| Instant Download Pdf
1. Which of the following is the primary safety concern during demolition
of a building?
A. Cost of materials
B. Structural collapse
C. Scheduling delays
D. Painting surfaces
Rationale: The greatest risk in demolition is uncontrolled structural
collapse, which can lead to severe injuries or fatalities.
2. Before starting demolition, what is the first step?
A. Begin removing walls
B. Obtain necessary permits and inspections
C. Start equipment setup
D. Dispose of debris
Rationale: Proper permits and inspections are required by law to
ensure safety and regulatory compliance.
3. What is the most appropriate method for demolishing a concrete wall in
a controlled manner?
A. Explosives without warning
B. Hydraulic breakers or jackhammers
C. Manual hammering only
D. Burning
Rationale: Controlled mechanical methods reduce risk and ensure
structural elements are removed safely.
,4. Which type of demolition involves dismantling a structure piece by
piece?
A. Implosion
B. Selective demolition
C. Wrecking ball demolition
D. High-reach demolition
Rationale: Selective demolition targets specific areas or components
for removal while preserving others.
5. What must be done to ensure electrical safety during demolition?
A. Cover all wires
B. Shut off and lock out all power sources
C. Wear gloves only
D. Keep water nearby
Rationale: Lockout/tagout procedures prevent accidental energizing
of circuits, reducing electrocution risk.
6. When using explosives for demolition, who must be present?
A. Any construction worker
B. Licensed blasting professional
C. The project manager only
D. Neighbors
Rationale: Explosives require licensed specialists trained in handling
and safety protocols.
7. Which equipment is commonly used to demolish steel structures?
A. Chainsaws
B. Oxy-acetylene torches and hydraulic shears
C. Sledgehammers only
D. Water jets
Rationale: Cutting tools like torches and shears are effective for steel
while controlling sparks and debris.
8. What type of soil testing is important before demolishing a structure?
A. pH testing
B. Load-bearing capacity testing
C. Fertility testing
D. Color testing
Rationale: Knowing soil strength ensures proper support and
prevents unexpected collapses during demolition.
, 9. What is the primary purpose of dust control during demolition?
A. Reduce noise
B. Protect workers and the surrounding environment
C. Increase demolition speed
D. Improve visual aesthetics
Rationale: Dust can carry harmful particulates; water sprays or
barriers reduce inhalation and environmental impact.
10. Which of the following is considered hazardous material that
must be removed before demolition?
A. Wood panels
B. Asbestos insulation
C. Drywall
D. Concrete blocks
Rationale: Asbestos is highly toxic; it must be safely removed and
disposed of following regulations.
11. What is the recommended method for disposing of demolition
debris?
A. Burn onsite
B. Transport to approved disposal sites or recycling facilities
C. Leave it at the roadside
D. Dump in water bodies
Rationale: Proper disposal prevents environmental contamination
and adheres to legal requirements.
12. What does a pre-demolition survey include?
A. Estimating project cost only
B. Assessing structure, hazards, and materials
C. Selecting demolition crew
D. Renting equipment
Rationale: Surveys identify risks, structural concerns, and hazardous
materials before work begins.
13. During interior demolition, which type of demolition is most
efficient?
A. Implosion
B. Hand demolition with selective removal
C. Wrecking ball
D. High-reach excavator
Questions And Correct Answers
(Verified Answers) Plus Rationale2026
Q&A| Instant Download Pdf
1. Which of the following is the primary safety concern during demolition
of a building?
A. Cost of materials
B. Structural collapse
C. Scheduling delays
D. Painting surfaces
Rationale: The greatest risk in demolition is uncontrolled structural
collapse, which can lead to severe injuries or fatalities.
2. Before starting demolition, what is the first step?
A. Begin removing walls
B. Obtain necessary permits and inspections
C. Start equipment setup
D. Dispose of debris
Rationale: Proper permits and inspections are required by law to
ensure safety and regulatory compliance.
3. What is the most appropriate method for demolishing a concrete wall in
a controlled manner?
A. Explosives without warning
B. Hydraulic breakers or jackhammers
C. Manual hammering only
D. Burning
Rationale: Controlled mechanical methods reduce risk and ensure
structural elements are removed safely.
,4. Which type of demolition involves dismantling a structure piece by
piece?
A. Implosion
B. Selective demolition
C. Wrecking ball demolition
D. High-reach demolition
Rationale: Selective demolition targets specific areas or components
for removal while preserving others.
5. What must be done to ensure electrical safety during demolition?
A. Cover all wires
B. Shut off and lock out all power sources
C. Wear gloves only
D. Keep water nearby
Rationale: Lockout/tagout procedures prevent accidental energizing
of circuits, reducing electrocution risk.
6. When using explosives for demolition, who must be present?
A. Any construction worker
B. Licensed blasting professional
C. The project manager only
D. Neighbors
Rationale: Explosives require licensed specialists trained in handling
and safety protocols.
7. Which equipment is commonly used to demolish steel structures?
A. Chainsaws
B. Oxy-acetylene torches and hydraulic shears
C. Sledgehammers only
D. Water jets
Rationale: Cutting tools like torches and shears are effective for steel
while controlling sparks and debris.
8. What type of soil testing is important before demolishing a structure?
A. pH testing
B. Load-bearing capacity testing
C. Fertility testing
D. Color testing
Rationale: Knowing soil strength ensures proper support and
prevents unexpected collapses during demolition.
, 9. What is the primary purpose of dust control during demolition?
A. Reduce noise
B. Protect workers and the surrounding environment
C. Increase demolition speed
D. Improve visual aesthetics
Rationale: Dust can carry harmful particulates; water sprays or
barriers reduce inhalation and environmental impact.
10. Which of the following is considered hazardous material that
must be removed before demolition?
A. Wood panels
B. Asbestos insulation
C. Drywall
D. Concrete blocks
Rationale: Asbestos is highly toxic; it must be safely removed and
disposed of following regulations.
11. What is the recommended method for disposing of demolition
debris?
A. Burn onsite
B. Transport to approved disposal sites or recycling facilities
C. Leave it at the roadside
D. Dump in water bodies
Rationale: Proper disposal prevents environmental contamination
and adheres to legal requirements.
12. What does a pre-demolition survey include?
A. Estimating project cost only
B. Assessing structure, hazards, and materials
C. Selecting demolition crew
D. Renting equipment
Rationale: Surveys identify risks, structural concerns, and hazardous
materials before work begins.
13. During interior demolition, which type of demolition is most
efficient?
A. Implosion
B. Hand demolition with selective removal
C. Wrecking ball
D. High-reach excavator
