NFPA 921 Fire Investigation Flashcards

NFPA 921 requires that fire investigators apply which systematic approach to their investigations?

Answer: The scientific method

NFPA 921 mandates the use of the scientific method, which involves recognizing the problem, defining it, collecting data, analyzing data, and forming a hypothesis.

In NFPA 921's scientific method, what must happen after a hypothesis is formed?

Answer: It must be tested against all collected data

The hypothesis must be tested against all known data; if it cannot withstand testing, it must be revised or rejected.

Which of the following best describes 'negative corpus' as addressed in NFPA 921?

Answer: Classifying a fire as incendiary by eliminating accidental causes without positive proof

NFPA 921 explicitly warns that classifying a fire as incendiary solely by eliminating other causes, without positive evidence of incendiary origin, is not scientifically valid.

What is 'low burn' and what is its investigative significance per NFPA 921?

Answer: Char or burn damage close to the floor; may indicate fire origin at that level

Low burn refers to char and fire damage near the floor, which can indicate where fire originated but must be evaluated with all other evidence before drawing conclusions.

Per NFPA 921, which of the following is a common fire pattern that helps determine the direction of fire travel?

Answer: Char depth variation across structural members

Greater char depth on structural members generally indicates longer exposure to heat, helping investigators trace the direction from which fire traveled.

According to NFPA 921, when multiple fire origins are identified with no apparent connection, the investigator should consider:

Answer: The possibility of an incendiary fire

Multiple unconnected areas of origin are a significant indicator of an incendiary fire, because accidental fires typically have a single origin.

NFPA 921 recommends documentation of the fire scene using which combination of methods?

Answer: Photography, videography, diagrams, and written notes

NFPA 921 recommends a comprehensive documentation approach combining photography, video, measured diagrams, and written notes to capture all scene details.