| Grade | Specific outside diameter D mm (in) | Percentage of the specified minimum yield stress to determine S | |
| Standard pressure test | Alternative pressure test | ||
| A25 | 141.3 (5.563) | 60 | - |
| A | ≥60.3 (2.375) | 60 | 75 |
| B | ≥60.3 (2.375) | 60 | 75 |
| X42 to X80 | ≤141.3 (5.563) | 60 | 75 |
| >141.3 (5.563) a ≤219.1 (8.625) | 75 | 75 | |
| >219.1 (8.625) a <508 (20.00) | 85 | 85 | |
| ≥508 (20.00) | 90 | 90 | |