Which expansion correctly defines the mnemonic FISHED?

• A. Friction, Impact, Shock, Heat, Electronic, Discharge
• B. Friction, Ice, Shock, Heat, Electron, Discharge
• C. Fuels, Initiation, Shock, Heat, Electronic, Discharge
• D. Friction, Impact, Spark, Heat, Electronic, Detonation

Answer: (A)

FISHED is a mnemonic used to remember the common ways energetic materials can be ignited. Each letter points to a specific initiation source: Friction, Impact, Shock, Heat, Electronic, and Discharge. Friction refers to heat generated by rubbing surfaces together; Impact means a blunt force causing initiation; Shock is a sudden pressure wave that can trigger ignition; Heat is a high temperature sufficient to ignite; Electronic covers electrical energy that can initiate, and Discharge specifically calls out the release of stored electrical energy, like a spark or arc.

The expansion Friction, Impact, Shock, Heat, Electronic, Discharge matches these categories exactly, which is why it is the best fit. Other options introduce terms that aren’t initiation sources in this mnemonic—Ice, Fuels, Spark, or Detonation—so they don’t align with the sequence or the intended categories of ignition sources.