Which of the following terms best describes an explosive hazard?

The term "high explosive" best describes an explosive hazard because it refers specifically to materials that have a high rate of reaction and produce a shock wave when detonated. High explosives can cause significant damage and pose serious risks to safety due to their powerful nature. They are designed to detonate rather than deflagrate, meaning they create a rapid and violent explosion, which directly correlates with the concept of an explosive hazard.

In contrast, "low explosive" refers to substances that burn relatively slowly and produce lower-pressure waves. Although low explosives can also be hazardous, their effects are typically less destructive than those of high explosives. "Safety procedure" refers to the measures and practices instituted to minimize risks and ensure safety, and while important, it does not define an explosive hazard. Lastly, "ground circuit" pertains to electrical systems and does not relate directly to explosive materials. Hence, high explosives are characterized by their potential to create significant explosive hazards, making it the accurate choice in this context.