TN Blasting Test Study Guide Exam with
Questions and Verified Answers and Rationale
Question 1: According to Tennessee blasting regulations, what is the minimum distance required
between an explosive magazine and any inhabited building or highway, as specified by the American
Table of Distances?
A. The distance is determined solely by local municipal zoning laws.
B. The required distance increases proportionally with the total quantity of explosive materials stored.
C. A fixed distance of 500 feet applies regardless of explosive mass or shielding.
D. Storage distance regulations apply only to permanent underground storage facilities.
CORRECT ANSWER: B. The required distance increases proportionally with the total quantity of
explosive materials stored.
Rationale: The American Table of Distances (ATD) sets mandatory minimum safety distances between
explosive storage magazines and inhabited structures, public highways, and passenger railways. These
distances are scaled based on the total net explosive weight stored to mitigate blast wave and fragment
hazards in the event of accidental detonation.
Question 2: Under Tennessee law, what state authority is primarily responsible for issuing licenses to
blasters and enforcing state explosives regulations?
A. The Tennessee Department of Environment and Conservation (TDEC)
B. The Tennessee Department of Transportation (TDOT)
C. The State Fire Marshal's Office within the Tennessee Department of Commerce and Insurance
D. The Tennessee Highway Patrol
CORRECT ANSWER: C. The State Fire Marshal's Office within the Tennessee Department of Commerce
and Insurance
Rationale: The Tennessee Non-Electric and Electric Blasting Standards Act empowers the State Fire
Marshal’s Office (Department of Commerce and Insurance) to regulate explosive distribution, licensing of
blasters, magazine registration, and safety enforcement across the state.
Question 3: When electric detonators are used on a blast site, which condition poses the most
immediate hazard of premature initiation?
A. High ambient relative humidity exceeding 85%
,B. Stray electric currents or radio frequency (RF) energy from nearby transmitters
C. Use of heavy non-conductive plastic stemments
D. Moderate wind speed across the blast field
CORRECT ANSWER: B. Stray electric currents or radio frequency (RF) energy from nearby transmitters
Rationale: Electric detonators rely on low electrical thresholds to ignite the bridge wire. Stray ground
currents, static electricity, lightning, or high-power radio frequency transmissions can induce sufficient
current in the leg wires to trigger premature detonation.
Question 4: What is the primary function of stemming material placed in the top section of a blast
borehole?
A. To dilute the chemical concentration of toxic detonation fumes
B. To confine the detonation gases, maximizing fracture efficiency and reducing flyrock
C. To prevent moisture from entering the lower explosive charge column
D. To absorb ground vibrations before they propagate outward
CORRECT ANSWER: B. To confine the detonation gases, maximizing fracture efficiency and reducing
flyrock
Rationale: Stemming—typically clean, crushed stone or aggregate—plugs the upper portion of a
borehole. Proper confinement keeps high-pressure detonation gases within the rock mass longer,
improving rock breakage while preventing airblast and dangerous flyrock from escaping out the top of
the hole.
Question 5: Which instrument is standard for measuring ground vibration and air overpressure
resulting from commercial blasting activities?
A. Anemometer
B. Piezometer
C. Peak Particle Velocity (PPV) Seismograph
D. Inclinometer
CORRECT ANSWER: C. Peak Particle Velocity (PPV) Seismograph
Rationale: Blast monitoring seismographs measure seismic wave velocity (Peak Particle Velocity in inches
or millimeters per second) across three axes (radial, vertical, and transverse) as well as sound pressure
levels (airblast dB) to ensure compliance with legal damage thresholds.
Question 6: In blast design, what is the definition of "burden"?
,A. The total weight of explosives loaded into a single borehole.
B. The distance from an explosive charge to the nearest free face of the rock.
C. The distance measured between adjacent boreholes within the same row.
D. The vertical height of the bench measured from top to floor.
CORRECT ANSWER: B. The distance from an explosive charge to the nearest free face of the rock.
Rationale: Burden is defined as the distance from the borehole charge to the nearest open or free face.
Proper burden calculation ensures optimal rock fragmentation and gas expansion without generating
excessive flyrock or ground vibration.
Question 7: Under ATF regulations for explosive storage, Type 1 magazines are primarily designed for
which type of storage?
A. Temporary outdoor storage of explosive materials during daylight hours only.
B. Indoor storage of low explosives not exceeding 50 pounds total weight.
C. Permanent storage of high explosives and detonators.
D. Mobile transport of explosive materials between active blast sites.
CORRECT ANSWER: C. Permanent storage of high explosives and detonators.
Rationale: Type 1 magazines are bullet-resistant, fire-resistant, weather-resistant, theft-resistant, and
ventilated structures designed specifically for permanent storage of high explosives and detonator
products.
Question 8: Which chemical compound or mixture serves as the oxidizer component in standard ANFO
explosive blenders?
A. Fuel oil #2
B. Sodium nitrate
C. Ammonium nitrate
D. Nitroglycerin
CORRECT ANSWER: C. Ammonium nitrate
Rationale: ANFO consists of approximately 94% ammonium nitrate (which acts as the oxidizing agent)
and 6% fuel oil (which acts as the fuel source).
Question 9: What is the purpose of using delay detonators in multi-hole blast designs rather than firing
all holes simultaneously?
, A. To lower the overall cost of initiation equipment.
B. To reduce peak ground vibration levels and control rock movement direction.
C. To prevent water from penetrating surrounding uncharged boreholes.
D. To eliminate toxic fumes emitted by the explosive reaction.
CORRECT ANSWER: B. To reduce peak ground vibration levels and control rock movement direction.
Rationale: Staggering hole detonations using millisecond delays reduces the total explosive energy
detonating at any single instance, significantly lowering peak particle velocity (PPV) ground vibrations
and improving burden displacement.
Question 10: According to standard safety guidelines, what action must a blaster take if a misfire is
suspected after firing a blast?
A. Immediately drill out the misfired hole using a high-speed pneumatic drill.
B. Wash out the borehole using high-pressure water or compressed air immediately.
C. Evacuate the area, wait the required mandatory safety period, and inspect under qualified
supervision.
D. Re-fire the circuit immediately without investigating the cause.
CORRECT ANSWER: C. Evacuate the area, wait the required mandatory safety period, and inspect
under qualified supervision.
Rationale: When a misfire occurs or is suspected, safety regulations require clearing the area and waiting
a mandatory waiting period (typically 15–30 minutes depending on initiation system type) before a
licensed blaster safely evaluates and clears the misfire.
Question 11: What is the term for the maximum vibration frequency limit measured in inches per
second (ips) used to evaluate potential structural damage to residential dwellings?
A. Scaled Distance Factor (SDF)
B. Peak Particle Velocity (PPV)
C. Decibel Noise Reduction Rating (NRR)
D. Detonation Pressure Index (DPI)
CORRECT ANSWER: B. Peak Particle Velocity (PPV)
Rationale: Peak Particle Velocity (PPV), expressed in inches per second (ips) or millimeters per second
(mm/s), is the industry standard parameter for assessing ground vibration intensity and structural
response.
Questions and Verified Answers and Rationale
Question 1: According to Tennessee blasting regulations, what is the minimum distance required
between an explosive magazine and any inhabited building or highway, as specified by the American
Table of Distances?
A. The distance is determined solely by local municipal zoning laws.
B. The required distance increases proportionally with the total quantity of explosive materials stored.
C. A fixed distance of 500 feet applies regardless of explosive mass or shielding.
D. Storage distance regulations apply only to permanent underground storage facilities.
CORRECT ANSWER: B. The required distance increases proportionally with the total quantity of
explosive materials stored.
Rationale: The American Table of Distances (ATD) sets mandatory minimum safety distances between
explosive storage magazines and inhabited structures, public highways, and passenger railways. These
distances are scaled based on the total net explosive weight stored to mitigate blast wave and fragment
hazards in the event of accidental detonation.
Question 2: Under Tennessee law, what state authority is primarily responsible for issuing licenses to
blasters and enforcing state explosives regulations?
A. The Tennessee Department of Environment and Conservation (TDEC)
B. The Tennessee Department of Transportation (TDOT)
C. The State Fire Marshal's Office within the Tennessee Department of Commerce and Insurance
D. The Tennessee Highway Patrol
CORRECT ANSWER: C. The State Fire Marshal's Office within the Tennessee Department of Commerce
and Insurance
Rationale: The Tennessee Non-Electric and Electric Blasting Standards Act empowers the State Fire
Marshal’s Office (Department of Commerce and Insurance) to regulate explosive distribution, licensing of
blasters, magazine registration, and safety enforcement across the state.
Question 3: When electric detonators are used on a blast site, which condition poses the most
immediate hazard of premature initiation?
A. High ambient relative humidity exceeding 85%
,B. Stray electric currents or radio frequency (RF) energy from nearby transmitters
C. Use of heavy non-conductive plastic stemments
D. Moderate wind speed across the blast field
CORRECT ANSWER: B. Stray electric currents or radio frequency (RF) energy from nearby transmitters
Rationale: Electric detonators rely on low electrical thresholds to ignite the bridge wire. Stray ground
currents, static electricity, lightning, or high-power radio frequency transmissions can induce sufficient
current in the leg wires to trigger premature detonation.
Question 4: What is the primary function of stemming material placed in the top section of a blast
borehole?
A. To dilute the chemical concentration of toxic detonation fumes
B. To confine the detonation gases, maximizing fracture efficiency and reducing flyrock
C. To prevent moisture from entering the lower explosive charge column
D. To absorb ground vibrations before they propagate outward
CORRECT ANSWER: B. To confine the detonation gases, maximizing fracture efficiency and reducing
flyrock
Rationale: Stemming—typically clean, crushed stone or aggregate—plugs the upper portion of a
borehole. Proper confinement keeps high-pressure detonation gases within the rock mass longer,
improving rock breakage while preventing airblast and dangerous flyrock from escaping out the top of
the hole.
Question 5: Which instrument is standard for measuring ground vibration and air overpressure
resulting from commercial blasting activities?
A. Anemometer
B. Piezometer
C. Peak Particle Velocity (PPV) Seismograph
D. Inclinometer
CORRECT ANSWER: C. Peak Particle Velocity (PPV) Seismograph
Rationale: Blast monitoring seismographs measure seismic wave velocity (Peak Particle Velocity in inches
or millimeters per second) across three axes (radial, vertical, and transverse) as well as sound pressure
levels (airblast dB) to ensure compliance with legal damage thresholds.
Question 6: In blast design, what is the definition of "burden"?
,A. The total weight of explosives loaded into a single borehole.
B. The distance from an explosive charge to the nearest free face of the rock.
C. The distance measured between adjacent boreholes within the same row.
D. The vertical height of the bench measured from top to floor.
CORRECT ANSWER: B. The distance from an explosive charge to the nearest free face of the rock.
Rationale: Burden is defined as the distance from the borehole charge to the nearest open or free face.
Proper burden calculation ensures optimal rock fragmentation and gas expansion without generating
excessive flyrock or ground vibration.
Question 7: Under ATF regulations for explosive storage, Type 1 magazines are primarily designed for
which type of storage?
A. Temporary outdoor storage of explosive materials during daylight hours only.
B. Indoor storage of low explosives not exceeding 50 pounds total weight.
C. Permanent storage of high explosives and detonators.
D. Mobile transport of explosive materials between active blast sites.
CORRECT ANSWER: C. Permanent storage of high explosives and detonators.
Rationale: Type 1 magazines are bullet-resistant, fire-resistant, weather-resistant, theft-resistant, and
ventilated structures designed specifically for permanent storage of high explosives and detonator
products.
Question 8: Which chemical compound or mixture serves as the oxidizer component in standard ANFO
explosive blenders?
A. Fuel oil #2
B. Sodium nitrate
C. Ammonium nitrate
D. Nitroglycerin
CORRECT ANSWER: C. Ammonium nitrate
Rationale: ANFO consists of approximately 94% ammonium nitrate (which acts as the oxidizing agent)
and 6% fuel oil (which acts as the fuel source).
Question 9: What is the purpose of using delay detonators in multi-hole blast designs rather than firing
all holes simultaneously?
, A. To lower the overall cost of initiation equipment.
B. To reduce peak ground vibration levels and control rock movement direction.
C. To prevent water from penetrating surrounding uncharged boreholes.
D. To eliminate toxic fumes emitted by the explosive reaction.
CORRECT ANSWER: B. To reduce peak ground vibration levels and control rock movement direction.
Rationale: Staggering hole detonations using millisecond delays reduces the total explosive energy
detonating at any single instance, significantly lowering peak particle velocity (PPV) ground vibrations
and improving burden displacement.
Question 10: According to standard safety guidelines, what action must a blaster take if a misfire is
suspected after firing a blast?
A. Immediately drill out the misfired hole using a high-speed pneumatic drill.
B. Wash out the borehole using high-pressure water or compressed air immediately.
C. Evacuate the area, wait the required mandatory safety period, and inspect under qualified
supervision.
D. Re-fire the circuit immediately without investigating the cause.
CORRECT ANSWER: C. Evacuate the area, wait the required mandatory safety period, and inspect
under qualified supervision.
Rationale: When a misfire occurs or is suspected, safety regulations require clearing the area and waiting
a mandatory waiting period (typically 15–30 minutes depending on initiation system type) before a
licensed blaster safely evaluates and clears the misfire.
Question 11: What is the term for the maximum vibration frequency limit measured in inches per
second (ips) used to evaluate potential structural damage to residential dwellings?
A. Scaled Distance Factor (SDF)
B. Peak Particle Velocity (PPV)
C. Decibel Noise Reduction Rating (NRR)
D. Detonation Pressure Index (DPI)
CORRECT ANSWER: B. Peak Particle Velocity (PPV)
Rationale: Peak Particle Velocity (PPV), expressed in inches per second (ips) or millimeters per second
(mm/s), is the industry standard parameter for assessing ground vibration intensity and structural
response.
