PPL pipe spools have the following nominal liner thickness:
| Sizes | PPL Liner Thickness In. |
Vacuum Rating (in Hg/F) |
| 1" | .135 | FV @ 225°F |
| 1-1/2" | .160 | FV @ 225°F |
| 2" | .175 | FV @ 225°F |
| 3" | .175 | FV @ 225°F |
| 4" | .210 | FV @ 225°F |
| 6" | .220 | FV @ 225°F |
| 8" | .310 | FV @ 225°F |
| 10" | .320 | FV @ 225°F |
| 12" | .380 | FV @ 225°F |
FV = Full Vacuum
Liner is orange or unpigmented in color.