Rationale

The scope and rationale of this project are the following: • Add requirement that the apparent ring tensile strength test be conducted at 73.4°F (23°C) only. • Revised X1.1, X1.2 and X1.3 for clarity, fixing X1.3 which incorrectly states that the only SDR mentioned in Table 1 is SDR 9. • Revise X3 to remove eight instances of mandatory language. • Reduce frequency of recommended quick burst test at elevated temperatures in X3.