Certain ASTM standard specifications were given to welded pipe fittings recently covering various aspects of fittings for high-temperature service, special applications like fire protection use and other ordinary services. These standards are given in the table below:
| A234 | A234/A234M-99 | Piping Fittings of Wrought Carbon Steel and Alloy Steel for Moderate and High Temperature Service |
| A403 | A403/A403M-99a | Wrought Austenitic Stainless Steel Piping Fittings |
| A420 | A420/A420M-99 | Piping Fittings of Wrought Carbon Steel and Alloy Steel for Low-Temperature Service |
| A774 | A774/A774M-98 | As-Welded Wrought Austenitic Stainless Steel Fittings for General Corrosive Service at Low and Moderate Temperatures |