Practice question

An LEL reading of 100% on a 4-gas meter means:

  1. The atmosphere is at exactly 1% of the lower explosive limit
  2. The atmosphere is at the lower explosive limit of the calibration gas — ignition is possible
  3. Oxygen is depleted
  4. The meter has malfunctioned

Answer: B — The atmosphere is at the lower explosive limit of the calibration gas — ignition is possible

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