Sunday, March 10, 2013

What water filter does the military use?

This piece of news jumped at my attention immediately, partly because of the connection to the U.S. Military. Items used by them (military specifications or milspec) are usually quite good and certainly up to the rigours of combat and heavy outdoors use.

Water Purifier Meets Requirements of US Military Small Unit Tests (28 Feb 2013)

Figure: Seldon Technologies WaterBox™ 300 MIL ( Look closely at the left compartment and you will see 3 filters (within seemingly conventional housing) with labels (jack up your magnification to see clearly). R to L: some sort of pleated sediment filter; some sort of depth filter (melt blown?) to remove smaller sediments and protect the main filter; the main filter and the star of the show - a nanofilter made into a mesh of carbon nanotubes hence giving rise to nanometer sized pores (

I have extracted some of its highlights from

  • Setup time is under five minutes
  • Requires no maintenance, no chemicals, and no heat to operate
  • No waste water is generated as a result of the purification process
  • Removes bacteria, viruses, Cryptosporidium, and Giardia to USEPA drinking water standards: 99.9999% of bacteria, 99.99% of viruses, and 99.9% of cysts
  • Reduces sediments, chlorine, total organic carbons, bad taste, and odors
  • Reduces chemicals and many harmful heavy metals (e.g., mercury and lead)
  • Self-priming system can pump from any water source with up to 4.3 meters (14 feet) of lift
  • Patented Nanomesh technology for high-performance contaminant removal

  • Capacity: up to 30,000 liters (8,000 gallons), depending on water quality
  • Flow rate: 1.89 liters (0.5 gallons) per minute
  • Weight: 78 pounds (31.8 kg)
  • Power source: 12VDC, 24VDC, 115VAC 60-Hz, or 230VAC 50-Hz

Looks good. Their Nanomesh technology is a form of nanofiltration. In simple terms, it can filter off particles down to nanometers in size, meaning most microbes and many types of molecules and ions (the big ones). NOTE that it is not designed to filter off sodium chloride which is the salt in seawater so it is not for desalination.

It can accept DC and AC from the more common voltages. BUT it still needs electricity basically to run the pump (top left on the right compartment). Meaning that in a grid down situation that you and I are likely to face in an emergency, this thingy will just sit pretty there. On the other hand, I believe, Seldon Technologies has a version that works on manual pumping. (Check out my previous posts on an alternative water filter for emergencies: Do we really need water filters 2?, Do we really need water filters?, Introducing the British Berkefeld filter - something you can count on when the chips are down)

Weight of 31.8kg is not exactly a walk in the park to carry around so plan on having a helper or a trolley if you want to move it around much. Capacity of up to 30000L (before replacement of the main filter?) is pretty impressive, considering that a person needs 2L per day for purely survival mode (no sweating and jumping around). A flowrate of 1.89L/min is quite decent for a small group, similar to a squad of Navy Seals or Special Forces that this filter is designed for.

No comments: