What is the summation of two standard 90-degree turns in a drain line's total effective length?

The total effective length of a drain line is impacted by the addition of fittings, such as standard 90-degree turns. Each standard 90-degree turn typically adds a certain amount of length to the pipe system due to its curvature and the way it redirects flow.

In plumbing, it's common to consider that a standard 90-degree turn contributes approximately 5 feet to the effective length of the drain line. Therefore, when calculating the total effective length from two such turns, you would add the 5 feet from the first turn to the 5 feet from the second turn. This totals 10 feet of effective length.

Therefore, the correct answer reflects this summation, confirming that the total effective length added by two standard 90-degree turns is 10 feet. Understanding how fittings like elbows and turns influence total effective lengths is crucial for precise plumbing system design and flow calculations.