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Harriette Purchas gravatar image
RedR TSS

What is the reason behind the desired change?

There are some benefits that you get with Lifestraws and similar filtration based products that you won’t get with chemical disinfectants like Aquatabs Aquatabs for example have not been proven effective against Cryptosporidium oocysts. For this reason, if water to be treated by Aquatabs is likely to have been contaminated by sheep, cattle, etc. I would recommend boiling or ultrafiltration prior to using the Aquatabs for residual disinfection.

Turbidity and suspended solids can also shield pathogens from disinfection, I therefore wouldn’t recommend Aquatabs or similar on turbid or coloured water unless it is first adequately filtered. Lifestraws and similar disinfect by filtration, hence they can be used directly with turbid water.

Another potential issue with chemical disinfectants is that they require a certain concentration for a certain length of time to disinfect the water. Aquatabs require 30-60 minutes and it is important that the volume of water that they are designed to treat is not significantly exceeded. Point of use personal filtration devices like Lifestraws are, in my opinion, more foolproof - generally speaking if you can suck the water with the normal resistance they are working normally. Unfortunately it’s not quite as clear cut with the larger Family units although water coming out the blue tap should generally be OK.

There is certainly less risk of ingesting a Lifestraw than a tablet & emergency shelters don’t tend to come with high level cupboards so that you can keep disinfectants and medicines out of reach of children.

Conversely the big downside of point-of-use filtration devices like Lifestraws is the cost. If you have a short term disaster with clear water that only requires disinfection then chemical disinfection tablets like Aquatabs can save more lives for the same budget. That said, if you know the water is clear, that may be because it has been treated, in which case you would probably be even more cost effective disinfecting at point of treatment, if you can maintain disinfectant residual through to the point of use.

I don’t know about import issues - I could even envisage issues with some customs officials in clearing a large number of Lifestraws. I know one membrane manufacturer for example who didn’t sell their ultrafiltration product in the Middle East. Export regulations on equipment capable of enrichment were cited as the reason… Unless others have a feel for this, perhaps a logs expert may be better placed to comment.

It would be helpful to know the exact context and motivation for moving from Lifestraws so that we can recommend specific solutions that overcome the specific issues. There are plenty contexts in which neither LifeStraws nor Aquatabs would be appropriate, and I would say that some form of water safety plan is required every time.

Kind regards

Martin