I am installing a garage heater. I did my homework and learned how to calculate pipe capacity and arrived at a plan. Now however, upon reading the installation instructions for CSST it refers to Effective Hydraulic Diameter, and has separate tables for CSST versus Black Pipe. The tables don't use equivalent values so I cannot tell for sure whether CSST has a different capacity compared to iron pipe.

I did my calculations a month ago using what I thought were universal tables for pipe size. Do I need to recalculate everything using special values for CSST?

(Glad I haven't cut anything yet) Thanks!