| PVC | Polyvinyl chloride |
| PE | Polyethylene |
| HDPE | High-density polyethylene (HDPE) |
| PEX | Cross-linked polyethylene |
| PA11 | Nylon 11 or polyamide 11 |
| PVDF | Polyvinylidene fluoride or polyvinylidene difluoride (PVDF) |
| PPT | Parts per trillion; PPT = PPM/1000 |
| PPM | Parts per million |
| UV | Ultraviolet |
| GRE | Glass-reinforced epoxy (composite) |
| SD | Standard deviation |
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