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NFPA 70E Electrical Hazard Safety Exam
2026/2027 Actual Exam | Ultimate 90 Answered
Questions with Proven Tips & Strategies for
Success | Pass Guaranteed - A+ Graded
Section 1: Electrical Safety Fundamentals
Q1: According to NFPA 70E, the limited approach boundary for a 480-volt exposed fixed circuit
part is:
A. 12 inches
B. 24 inches
C. 36 inches
D. 42 inches [CORRECT]
Correct Answer: D
Rationale: Per NFPA 70E Table 130.4(D)(a), for systems between 301V and 750V, the limited
approach boundary is 3 feet 6 inches (42 inches). This is the distance within which unqualified
persons must not stand.
Q2: The arc flash boundary is defined as the distance from an arc flash hazard where the incident
energy equals:
A. 1.2 cal/cm² [CORRECT]
B. 5.0 cal/cm²
C. 8.0 cal/cm²
D. 40.0 cal/cm²
Correct Answer: A
Rationale: The arc flash boundary is the distance at which the incident energy is calculated to be
1.2 calories per centimeter squared (cal/cm²), which is the threshold for the onset of a second-
degree burn on unprotected skin.
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Q3: Which of the following is NOT one of the three primary electrical hazards identified in
NFPA 70E?
A. Shock
B. Arc Flash
C. Arc Blast
D. Electromagnetic Interference [CORRECT]
Correct Answer: D
Rationale: The three primary electrical hazards addressed by NFPA 70E are electrical shock, arc
flash (thermal burns), and arc blast (pressure waves). While electromagnetic interference is an
electrical phenomenon, it is not classified as a primary safety hazard in this context.
Q4: If an unqualified person must enter the limited approach boundary, they must be:
A. Wearing Category 4 PPE
B. Continuously escorted by a qualified person [CORRECT]
C. Authorized in writing by management
D. Equipped with voltage-rated gloves
Correct Answer: B
Rationale: Unqualified persons are only allowed within the limited approach boundary if they are
continuously escorted by a qualified person and advised of the potential hazards. They do not
typically perform work requiring high-level PPE.
Q5: The restricted approach boundary for a 480-volt system is the distance within which:
A. Only qualified persons may enter
B. Unqualified persons may enter with PPE
C. Only qualified persons using proper PPE and work practices may enter [CORRECT]
D. No one is allowed under any circumstances
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Correct Answer: C
Rationale: The restricted approach boundary is the area closest to the exposed live parts. Only
qualified persons are allowed to enter, and they must use appropriate shock protection PPE (like
voltage-rated gloves) and safe work practices.
Q6: What is the restricted approach boundary distance for a system voltage of 480V?
A. 12 inches [CORRECT]
B. 24 inches
C. 36 inches
D. 42 inches
Correct Answer: A
Rationale: According to NFPA 70E Table 130.4(D)(a), for voltages between 301V and 750V, the
restricted approach boundary is 1 foot 0 inches (12 inches). This is closer than the limited
boundary.
Q7: The "prohibited approach boundary" found in older editions of NFPA 70E is now treated
similarly to:
A. The limited approach boundary
B. The restricted approach boundary [CORRECT]
C. The arc flash boundary
D. An unguarded live part
Correct Answer: B
Rationale: In recent editions of NFPA 70E, the prohibited approach boundary has been removed
to simplify the standard. The treatment of working very close to live parts is now covered under
the restricted approach boundary requirements.
, 4
Q8: An arc blast results from:
A. Direct contact with a conductor
B. The heating of air causing rapid expansion [CORRECT]
C. Chemical reaction with insulation
D. High-frequency radiation
Correct Answer: B
Rationale: An arc blast occurs because the temperature of an arc can reach 35,000°F. This
extreme heat causes rapid expansion of the surrounding air (copper also expands explosively),
creating a high-pressure wave or blast.
Q9: Which boundary is primarily concerned with thermal energy and burns?
A. Limited approach boundary
B. Restricted approach boundary
C. Arc flash boundary [CORRECT]
D. Shock protection boundary
Correct Answer: C
Rationale: The limited and restricted approach boundaries relate to shock hazards. The arc flash
boundary specifically relates to thermal energy (heat) and the distance required to prevent burns
to unprotected skin.
Q10: At what voltage level does NFPA 70E generally require an arc flash hazard analysis to be
performed?
A. 50 volts
B. 120 volts
C. Greater than 50 volts [CORRECT]
D. Greater than 600 volts
NFPA 70E Electrical Hazard Safety Exam
2026/2027 Actual Exam | Ultimate 90 Answered
Questions with Proven Tips & Strategies for
Success | Pass Guaranteed - A+ Graded
Section 1: Electrical Safety Fundamentals
Q1: According to NFPA 70E, the limited approach boundary for a 480-volt exposed fixed circuit
part is:
A. 12 inches
B. 24 inches
C. 36 inches
D. 42 inches [CORRECT]
Correct Answer: D
Rationale: Per NFPA 70E Table 130.4(D)(a), for systems between 301V and 750V, the limited
approach boundary is 3 feet 6 inches (42 inches). This is the distance within which unqualified
persons must not stand.
Q2: The arc flash boundary is defined as the distance from an arc flash hazard where the incident
energy equals:
A. 1.2 cal/cm² [CORRECT]
B. 5.0 cal/cm²
C. 8.0 cal/cm²
D. 40.0 cal/cm²
Correct Answer: A
Rationale: The arc flash boundary is the distance at which the incident energy is calculated to be
1.2 calories per centimeter squared (cal/cm²), which is the threshold for the onset of a second-
degree burn on unprotected skin.
,2
Q3: Which of the following is NOT one of the three primary electrical hazards identified in
NFPA 70E?
A. Shock
B. Arc Flash
C. Arc Blast
D. Electromagnetic Interference [CORRECT]
Correct Answer: D
Rationale: The three primary electrical hazards addressed by NFPA 70E are electrical shock, arc
flash (thermal burns), and arc blast (pressure waves). While electromagnetic interference is an
electrical phenomenon, it is not classified as a primary safety hazard in this context.
Q4: If an unqualified person must enter the limited approach boundary, they must be:
A. Wearing Category 4 PPE
B. Continuously escorted by a qualified person [CORRECT]
C. Authorized in writing by management
D. Equipped with voltage-rated gloves
Correct Answer: B
Rationale: Unqualified persons are only allowed within the limited approach boundary if they are
continuously escorted by a qualified person and advised of the potential hazards. They do not
typically perform work requiring high-level PPE.
Q5: The restricted approach boundary for a 480-volt system is the distance within which:
A. Only qualified persons may enter
B. Unqualified persons may enter with PPE
C. Only qualified persons using proper PPE and work practices may enter [CORRECT]
D. No one is allowed under any circumstances
,3
Correct Answer: C
Rationale: The restricted approach boundary is the area closest to the exposed live parts. Only
qualified persons are allowed to enter, and they must use appropriate shock protection PPE (like
voltage-rated gloves) and safe work practices.
Q6: What is the restricted approach boundary distance for a system voltage of 480V?
A. 12 inches [CORRECT]
B. 24 inches
C. 36 inches
D. 42 inches
Correct Answer: A
Rationale: According to NFPA 70E Table 130.4(D)(a), for voltages between 301V and 750V, the
restricted approach boundary is 1 foot 0 inches (12 inches). This is closer than the limited
boundary.
Q7: The "prohibited approach boundary" found in older editions of NFPA 70E is now treated
similarly to:
A. The limited approach boundary
B. The restricted approach boundary [CORRECT]
C. The arc flash boundary
D. An unguarded live part
Correct Answer: B
Rationale: In recent editions of NFPA 70E, the prohibited approach boundary has been removed
to simplify the standard. The treatment of working very close to live parts is now covered under
the restricted approach boundary requirements.
, 4
Q8: An arc blast results from:
A. Direct contact with a conductor
B. The heating of air causing rapid expansion [CORRECT]
C. Chemical reaction with insulation
D. High-frequency radiation
Correct Answer: B
Rationale: An arc blast occurs because the temperature of an arc can reach 35,000°F. This
extreme heat causes rapid expansion of the surrounding air (copper also expands explosively),
creating a high-pressure wave or blast.
Q9: Which boundary is primarily concerned with thermal energy and burns?
A. Limited approach boundary
B. Restricted approach boundary
C. Arc flash boundary [CORRECT]
D. Shock protection boundary
Correct Answer: C
Rationale: The limited and restricted approach boundaries relate to shock hazards. The arc flash
boundary specifically relates to thermal energy (heat) and the distance required to prevent burns
to unprotected skin.
Q10: At what voltage level does NFPA 70E generally require an arc flash hazard analysis to be
performed?
A. 50 volts
B. 120 volts
C. Greater than 50 volts [CORRECT]
D. Greater than 600 volts
