This highlighted and tabbed 2021 International Fuel Gas Code book will help you find the answers quickly. It is highlighted and tabbed for the PSI / NASCLA Contractor exams as well as the ICC Building Inspector exams. Description of the book – Addresses the design and installation of fuel gas systems and gas fired appliances through prescriptive and performance requirements. Key changes in the 2021 IFGC include: The termination of concealed condensate piping requires marking to indicate if it is the primary drain or the secondary drain. Press-connect joints are acceptable for high pressure (over 5 psig) applications indoors. Commercial cooking appliances are not allowed within dwelling units.