Certified Fire Investigator Practice Exam

What is meant by a "Bead" in electrical investigations?

1. A shiny surface on metal tools

2. A globule of metal created by arcing

3. A specific type of electrical component

4. A joint between wires in a circuit

The correct answer is: A globule of metal created by arcing

In the context of electrical investigations, a "Bead" refers specifically to a globule of metal created by arcing. When electrical current passes through a conductive material and there is a significant voltage difference, arcing can occur. This arcing generates intense heat, which can melt the metal at the point of contact, forming these small, often shiny droplets or beads of metal. These beads are critical indicators of electrical faults or failures during an investigation, as their presence can demonstrate where electrical arcing took place, indicating potential sources of ignition in fire incidents. Understanding the formation of beads helps investigators trace back the electrical flow and identify the conditions leading to a fire, aiding in the overall analysis of the fire’s origin and cause. The unique characteristics of these beads, including their shape and composition, can also provide insights into the electrical system involved, making them a crucial part of forensic examinations in electrical fire investigations.