Gas PipingQuestion 88 of 120
Measured along the pipe, the most remote gas outlet in a building is 78 ft from the meter. Sizing tables are printed in 10 ft length increments. Which length row should be used?
a.70 ft, because 78 is closer to 70 than to 90
b.75 ft, by interpolating between rows
c.80 ft, the next length greater than the measured length
d.78 ft, only if the table is redrawn to that value
Explanation
When the measured developed length falls between table rows, you use the next longer row, so 78 ft is sized from the 80 ft column. Rounding down to 70 ft would allow more pressure drop than the table assumes and undersize the pipe, and neither interpolating nor inventing a 78 ft row is permitted by the sizing method.
Law Reference: IFGC §402.4Practice all 120 questions free — no signup required.
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