LifeStraw® - Longevity and Efficacy

Laboratory test: Evaluation of Vestergaard Frandsen's hollow fiber LifeStraw® for the removal of Escherichia Coli and Cryptosporidium according to the US Environmental Protection Agency guide standard and protocol for evaluation of microbiological water purifiers

Partner: Naranjo, J. and Gerba, C.P. Department of Soil, Water and Environmental Science, University of Arizona, USA (2010)

Outcome:

Longevity of LifeStraw® was successfully assessed in laboratory conditions (harsher conditions than what is required by the EPA in terms of turbidity and organic matter), up to 1600L (approximately 160% of design life)

Backwash frequency used was once every 5L (corresponds to more or less a daily cleaning during real use)

Flow-rates varied as follows in average:

• 280mL/min at the beginning
• 280mL/min between 10 and 200L
• 250mL/min between 200 and 500L
• 170mL/min between 500 and 1000L
• 200 mL/min overall between 0 and 1000L

Antimicrobial efficacy of LifeStraw® was successfully assessed in the same laboratory conditions (EPA 1987 protocol for microbiological water purifiers testing) and showed that LifeStraw® meets the EPA requirements of LOG 6 reduction for bacteria and LOG 3 reduction for protozoan parasites:

*Note: results in Log reduction values (LRV)

Turbidity was removed during the challenges by 99.6% in average:

influent challenge water turbidity: 104 NTU

effluent challenge water turbidity: 0.4 NTU