Microbiological efficacy

  • The efficacy of durable and consumable HWTS products should demonstrate statistically significant reductions in microbiological contaminants over the life of the product.

Key indicators

  • Threshold for multistage device at end of life:
    • Bacterial efficacy: 3 log reduction value (LRV).
    • Viral efficacy: 3 LRV.
    • Cyst reduction: 2 LRV.
  • Most desirable for multi-stage device:
    • Bacterial efficacy: 6 LRV.
    • Viral efficacy: 4 LRV.
    • Cyst reduction: 3 LRV.

Notes and exceptions

  • There is a need for more health impact studies correlated to specific products or technologies.
  • Single-stage treatment methods may not meet a wide breadth of microbiological efficacy; however, the merit of the treatment should be assessed against available health impact studies.

Supporting evidence