Question 59Safety & Environmental - 1st Asst/Chief

The correct answer is A) As gas samples are drawn into the instrument they are burned within the case. This is correct because the meter shown in the illustration is a combustible gas detector, which works by drawing in a sample of the atmosphere and burning it within the instrument's case. The meter reading then indicates the concentration of combustible gases present. The other answer choices are incorrect because: B) Submerging the sampling tube in liquid would not provide an accurate reading, as the instrument is designed to sample the ambient atmosphere. C) A reading at the extreme right of the scale would indicate a high concentration of combustible gases, not a safe atmosphere. D) Meter readings are not instantaneous, as the instrument requires time to draw in and analyze the gas sample.