ASME B16.5-1996

Pipe Flanges & Flanged Fittings : NPS 1/2 Through NPS 24 (Includes 1998 Addenda)
standard by ASME International, 10/26/1998

ASME Y14.38-2019

Abbreviations and Acronyms for Use in Product Definition and Related Documents: Engineering Product Definition and Related Documentation Practices
standard by ASME International, 05/18/2020