Reference material
Treatment selection matrix
| Concern | Possible barrier | Proof to demand |
|---|---|---|
| Sediment | screen/media filter | micron/flow/pressure rating |
| Chlorine/taste | activated carbon | NSF 42 exact claim |
| Lead/health chemical | certified adsorption/RO | NSF 53/58 exact contaminant claim |
| Bacteria/protozoa | validated filter/UV/heat/chemical | NSF 55/P231 or specific performance |
| Viruses | validated purifier/UV/heat/chemical | specific virus reduction/inactivation |
| Salts/TDS | RO/distillation | NSF 58 and recovery/waste specs |
| Unknown chemicals | avoid source + test + targeted treatment | laboratory result and certified claim |