Explosives Safety & Handling Flashcards
7 cards from real CES practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Explosives Safety & Handling flashcards as text
What hazard classification does ANFO (ammonium nitrate/fuel oil) fall under per DOT regulations?
Answer: Division 1.5 – Very Insensitive Explosives
ANFO is classified as Division 1.5 (blasting agent/very insensitive explosive) because it requires a strong primer to initiate and does not detonate from standard shock or heat sources alone.
What is the purpose of a 'shunt' on electric blasting cap leg wires?
Answer: To short-circuit the leg wires and prevent accidental initiation from stray current
A shunt (short circuit across the leg wires) prevents stray electrical current from reaching the bridge wire and accidentally firing the cap during handling.
Which of the following explosive properties describes its resistance to accidental initiation by impact, heat, or friction?
Answer: Sensitivity
Sensitivity measures how easily an explosive can be initiated by external stimuli such as shock, heat, friction, or spark, which directly affects its handling safety.
What action must be taken if detonating cord becomes kinked or shows signs of physical damage before loading?
Answer: The damaged section must be cut out and discarded; the cord should not be used if the damage is severe
Kinks or damage in detonating cord can create weak points that interrupt propagation; damaged sections must be removed and severe damage warrants discarding the cord entirely.
Which document must accompany every shipment of explosive materials transported on public highways under DOT regulations?
Answer: A shipping paper (bill of lading) listing the proper shipping name, class, and quantity
DOT 49 CFR requires a shipping paper (bill of lading or manifest) listing the proper shipping name, hazard class, UN/NA number, and quantity for all hazardous materials shipments.
In a wet borehole, which product characteristic is MOST critical when selecting an explosive?
Answer: High water resistance to prevent desensitization
Water can desensitize many explosives by dissolving oxidizers or disrupting the fuel-oxidizer balance, so water-resistant formulations are essential in wet holes.
What is the correct procedure when a non-electric (shock tube) initiation system fails to fire?
Answer: Wait 30 minutes, then carefully examine the shock tube for breaks or disconnections before approaching the misfired charge
The mandatory wait time allows residual energy to dissipate; a broken or disconnected shock tube—not the charge itself—is the most common cause of non-electric system failures.