Summary of Topics s1091_6_sum.htmlSummary of Topics
The revisions to UL 1091 are being issued to:
Add Glossary, New Section 4A and Revise 5.1, 5.2, 6.1, 20.3, 21.2, 26.1, and Table 18.1 to Reference NPS or Nominal Pipe Size;
Add Guidelines for Conducting Operating Torque Value Calculations for Butterfly Valves to 20.6, and New Appendix A; and
Make Editorial Changes to Outside Standard References.