API RP 500

Recommended Practice for Classification of Locations for Electrical Installations at Petroleum Facilities Classified as Class I, Division 1, and Division 2, Fourth Edition
standard by American Petroleum Institute, 06/01/2023

API RP 6HT

Heat Treatment and Testing of Carbon, Micro-alloyed, and Low-alloy Steel Wrought and Cast Components, Third Edition
standard by American Petroleum Institute, 03/01/2023