Was reading up on the LIFESTRAW today and came across this information. It helps me understand some of the technicalities that I didn't before.
LifeStraw® - Acronyms/Definitions
Aging water: Water passed through the filter with determined known PH-TOC-total dissolved solids and turbidity to measure the filter’s resistance to clogging, flow-rate and lifetime.
CDC: Centers for Disease Control, USA.
CFU: Colony-Forming Unit (CFU) is a measure of viable bacterial numbers. It allows users to assess the degree of contamination in samples of water.
Challenge water: Water passed through the filter for microbiological efficacy tests. In this water, disinfectant is completely removed and residue level should be non-detectable. This is to ensure that there is no interference from residual chlorine (most tap water is chlorinated) on the contaminants introduced in the water and give a more accurate measure of the filter’s microbiological efficacy.
Environmental Protection Agency: The Environmental Protection Agency (EPA or USEPA) is an agency of the federal government of the United States charged with protecting human health and safeguarding the natural environment, namely air, water, and land.
Log reduction: -”LOG” stands for the logarithm function: 1, 2, 3 and 4 LOG reductions correspond to 90%, 99%, 99.9% and 99.99% reduction respectively, and so on.
LRV: Log Reduction Value.
Ms2: A virus which is easily cultivated in laboratories and used to measure viral reduction efficacy of the filter.
NSF International: The Public Health and Safety Company™, a not-for-profit, non-governmental organization based in the United States, is the world leader in standards development, product certification, education, and risk-management for public health and safety.
NTU: Nephelometric Turbidity Units. Turbidity refers to how clear the water is. The greater the amount of total suspended solids (TSS) in the water, the murkier it appears and the higher the measured turbidity.
PFU: Plaque-Forming Unit (PFU) is a measure of viable numbers of viruses in the water.
Point-of-use interventions: For those who have access to sufficient quantities of water but whose water is of poor microbiological quality, an alternative is to treat water at the household or other point of use. Such a household treatment may minimise recontamination in the home, a well-known cause of water quality degradation. Interventions used in the studies include: filtration (ceramic), solar disinfection, chlorination, flocculation/disinfection and improved storage.
RR: Rate of reduction.
RTC: Randomized Control Trial.
TOC: Total organic carbon: material in the water derived from decaying vegetation, bacterial growth, and metabolic activities of living organisms or chemicals.
TTC: Thermo Tolerant Coliforms
Turbidity: Turbidity is the cloudiness or haziness of a fluid caused by individual particles (suspended solids) that are generally invisible to the naked eye, similar to smoke in the air.
AND I found this as well.
(The below info is for the larger lifestraw FAMILY filter)
Microbiological Performance
Intervention Bacteria Virus Protozoan cyst Meets Environmental Protection Agency protocol
LifeStraw® Family Minimum 99.9999% Minimum 99.99% Minimum 99.9% Yes
Boiling 99.9999% 99.99% 99.9% Yes
Flocculation disinfection (Pur) 99.9999% 99.99% 99.9% Yes
Chlorination Depends upon the contact time and quantity of variable chlorine No
Bio sand filter 90%-99% 50%-90% 99.9% No
Ceramic filter >99% Low 99.9% No
Solar Distillation 99.999% 99.99% 50%-99% Unclear
Physical Performance
Intervention Water treatment capacity
Flow rate/processing time Factors affecting performance Impact on water taste/appearance Repeat intervention required
LifeStraw® Family 18,000 litres Average 9 litres/hour Safe storage if water not consumed directly Neutral for taste; positive for appearance No
Boiling Not applicable 20 minutes (includes heating water to 100°C, 1 min boiling, cooling) Boiling temperature and safe storage Neutral or negative for taste; neutral for appearance Yes
Flocculation disinfection
10 litres 30 minutes Exposure time, chemical concentration in mix Negative for taste; positive for appearance Yes
Chlorination (dilute NaOCl2)
1000 litres 30 minutes contact time after preparation and dosing Exposure time, turbidity, chlorine demand Negative Yes
Bio sand filter Up to 50 litres/day 0.1/0.3 metre/hour (when the average depth of sand filter is 0.7 metres) Proper construction, operation, and maintenance Neutral for taste; positive for appearance No
Ceramic filter 5000-10,000 litres 1-3 litres/hour Pore size and consistency; bacteriostatis; maintenance Neutral for taste; positive for appearance No
Solar Distillation
1-2 litre per bottle average 6 hours Sunlight, turbidity, dissolved solids Neutral for taste and appearance No
Last edited by SkunkHunter; 07/27/13 02:46 PM.