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Emergency Procedures and Response Flashcards

7 cards from real CNG practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 7 Emergency Procedures and Response flashcards as text

  1. In the United States, a CNG fuel release exceeding reportable quantity thresholds must be reported to:

    Answer: The National Response Center (NRC)

    The National Response Center (NRC) is the federally designated 24-hour reporting point for all significant hazardous material releases, including CNG.

  2. If a CNG vehicle overturns with an active gas leak, responders should:

    Answer: Isolate the area and eliminate all ignition sources

    Isolating the area and eliminating ignition sources prevents the gas from reaching flammable concentration near an ignition point.

  3. What physical property makes CNG inherently safer than gasoline in an outdoor spill scenario?

    Answer: CNG is lighter than air and disperses upward rather than pooling

    Being lighter than air, CNG rises and dilutes outdoors rather than pooling on the ground and spreading laterally like gasoline.

  4. The primary life-safety hazard during a CNG vehicle accident involving fuel release is:

    Answer: Fire or explosion resulting from ignition of released gas

    Natural gas is highly flammable within its 5–15% flammability range, making fire and explosion the dominant life-safety threat during a CNG release.

  5. At what concentration is natural gas (methane) classified as Immediately Dangerous to Life or Health (IDLH)?

    Answer: 150,000 ppm

    NIOSH establishes the IDLH for methane at 150,000 ppm (15% by volume), which corresponds to the lower explosive limit where asphyxiation and explosion risks converge.

  6. Before a CNG vehicle may return to service after an incident, which requirement must be met?

    Answer: An incident report and safety inspection certification must be completed

    An incident report documents what occurred, and a safety inspection certification confirms the CNG system is structurally sound and safe to operate.

  7. When calling 911 to report a CNG vehicle emergency, which information is MOST critical to provide first?

    Answer: The exact location and nature of the emergency

    Location and nature of the emergency are the most critical pieces of information so responders can dispatch appropriate resources to the right place.