Originally Posted by
Michael Larson
Michael,
I'm underlining different words which I think you may have missed.
Note: See Appendix for further explanatory material.
1. The minimum radius for the first 90 fitting downstream
from a trap serving a lavatory or sink shall be 1−3/4 for drain piping
1−1/2 in diameter. The fitting shall be a tee or quarter bend.
2. The minimum radius for the first 90 bend or elbow downstream
from a water closet shall be 2−1/2 for drain piping 3 in
diameter.
3. The minimum radius for the first 90 bend or elbow downstream
I doubt that is "the first" "90 degree fitting" (and that, to me, is even stretching the use of the phrase '90 degree fitting) "downstream from a trap" (that exception only applies to the first fitting after the trap) "serving a lavatory or sink" (what does that serve? a lavatory or a sink?).