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 minimum separation distance is required between a detonator magazine and a high explosives magazine under ATF regulations?
Answer: 100 feet
ATF regulations require a minimum of 100 feet separation between detonator (blasting cap) magazines and high explosives magazines to prevent sympathetic detonation.
Which condition makes it MOST dangerous to use electric blasting caps?
Answer: Proximity to radio frequency transmitters
Radio frequency energy from transmitters can induce stray currents in electric blasting cap leg wires, causing accidental initiation.
When conducting a post-blast inspection after a misfire, what is the FIRST action a blaster must take?
Answer: Wait at least 30 minutes before approaching in a hot blast and 1 hour for a cold blast
Waiting the mandated time (30 min for hot/warm blasts, 1 hour for cold/wet conditions) allows unstable material to stabilize before personnel approach.
Under OSHA 29 CFR 1926.912, when must all persons and vehicles be cleared from the blast area?
Answer: Before connecting the detonating circuit
OSHA requires all personnel and vehicles to be removed from the blast area before the blasting circuit is connected to prevent accidental initiation while people are present.
What does the term 'sympathetic detonation' refer to in explosives handling?
Answer: Detonation of one explosive charge triggered by the shock wave of an adjacent charge
Sympathetic detonation occurs when the shock energy from one exploding charge initiates a nearby unconnected charge without direct electrical or physical connection.
Which storage requirement applies specifically to black powder under 27 CFR Part 555?
Answer: It must be stored in a Type 4 magazine separate from high explosives
Black powder must be stored in a Type 4 magazine and kept separate from other explosive materials because it is more sensitive to heat and friction.
A blaster discovers an electric blasting cap leg wire has been cut during hole loading. What is the correct action?
Answer: Remove the cap from the hole carefully and treat it as a misfire
A damaged electric blasting cap must be carefully removed and treated as a misfire; splicing or bypassing it risks accidental detonation or a failed blast.