I was in the maket yesterday and I came across Pur water filters. It says that they can be used to remove biological contaminates from water and that I can Use them to desalinate sea water. Can these filters be trusted for solo filtration use or do I need other stuff. I still feel boiling and using solar destiller will be best way to go. Whats your experience with this. I am putting together a y2k prepareness organizer to help late GI's prepare quickly. Need your feedback on this one. Thanks

-- y2k aware mike (y2k aware mike @ conservation . com), July 05, 1999

Answers

Hi aware,

They are not good enough to use for serious contamination. The plus is fairly good but it more for common type of uses.Possibly for use with rainwater and that type of thing. Not for water from stream etc. There are some good portable ones at camping stores. The problem is you have to purchase filters and they are expensive.

-- Moore Dinty moore (not@thistime.com), July 05, 1999.

The March 1999 Gear Guide Issue of Backpacker Magazine praises PUR water filters:

"The Explorer is one of the best investments I ever made," says one of our equipment editors. 'It's durable, reliable, easy to clean in the field, and fast. And I've never had a failure that I couldn't fix.'

"The Hiker was also rated the easiest to use in "The water Filter Field Test" (December 1996) and was cited by at least three of our testers as their favorite filtering device.

In my opinion, a PUR water filter is great for backpacking an nice to have on hand for emergency usage. But I wouldn't want to use one (pumping, pumping and more pumping) daily for weeks at a time.

My first choice for a water filter is British Berkefeld's "Big Berkey." We use ours daily and think it's great. We put our through heavy usage daily and it produces clean, fresh tasting water.

You can read more about the Big Berkey at this website:

http://www.safe-water.com/ap/a273sw/index.html

What the Big Berkey filter will remove:

1. Absolute filtration efficiency to 0.5 microns. 2. For particles from 0.2 to 0.5 microns, filtration efficiency is greater than 98%. 3. Reduces turbidity (cloudiness) by an efficiency greater than 99.7%. 4. Independently tested to remove the following parasites and pathogenic bacteria:

E. Coli >99.99%

Klebsiella >99.99%

Cholera >99.99%

Shigella >99.99%

Salmonella >99.99%

Guinea Worm 100%

Giardia Lambia 100%

Cryptosporidium 100%

Big Berkey isn't cheap, but I think it's a good value. (Better than reverse osmosis.)

Boiling water, your first choice, Mike, may not always be the best way to go. It's time consuming and requires fuel. Some of the worst bugs in water require you to boil for up to 20 minutes (they used to think that 10 minutes was okay -- it's not). On a hot day like today (100+ degrees), who wants to boil water?

Not only that, if your water source is dirty -- as in brown -- boiling makes it safe-to-drink dirty water. The same is probably true of a PUR filter (I know it is for Katadyn -- which I own). A Big Berkey will remove the sediment. Pour in brown water, out comes crystal clear water.

Hope this helps.

-- walt (longyear@shentel.net), July 05, 1999.

Pur makes both water filters and water purifiers. Big difference. I have used the Pur Explorer and Voyager as my only source of water purification while backpacking for years and never had a problem. They both will leave a slight iodine taste to the water even if you use the charcoal filter. The Explorer is rated at about 100 Gallons per cartridge but that will decrease rapidly if you use murky water with out pre-filtering or settling.

IMHO use a purifier if you have any question about the water quality. They cost more than a water filter, made for making safe water taste better, but it is well worth it. You will also want a backup purifier such as Polar Pure incase the mechanical purifier craps out. And they do!

-- Jim (jimed@iglobal.net), July 05, 1999.

Im an experienced backpacker and did quite a bit of research on filters. We live in an apartment in a country area along a river, so my water solution is to purify. I picked up an MSR Miniworks and Waterworks, with enough filters to carry 1600 gallons. My friends have many types of filters which has given me some insight into their operation. Below are my impressions of each and why I bought an MSR.

For years I used a First Need, later went to a Sweetwater (now out of business). The First Need is a great filter but is heavy (consideration only to backpackers). Im not sure if it has a charcoal filter but it claims to be able to filter our some chemicals. It is somewhat awkward to use and I spilled my fresh water container more than once in the process of filtering. I then went to a Sweetwater but this had the annoying habit of spraying water when pumped to fast. First Need filters are hard to find and of course the Sweetwater is no longer made.

My requirements were thus; to have a filter that can be put into a puddle of excrement and pull out clean water. I wanted a bottle top adaptor like my Sweetwater, and a charcoal filter that would take out iodine/bleach, since the water might be treated like this prior to filtering. I have a good amount of respect for this aspect of survival. Ten years ago I was in the hospital for a week with what was probably a parasitic infection from the Catskills. I treated the water with iodine AND a filter, and still got sick. More than likely, a drop or aerosol particle of contaminated water got on the threads of a bottle being filled.

A friend has a Katadyn. Ive tried both models and they are VERY hard to force water through, but very durable. The disadvantage is that the Katadyn will not take out viruses and has no charcoal filter, which will take out some chemicals. The Katadyn mini has two models, regular filter and charcoal filter. Cant have both. The filters treat an emormous amount of water in their lifetime. I didnt buy a Katadyn because the filters are imported, and they are difficult to pump (I consider this important, after using my friends for 4 days). To treat for viruses and iodine I would have to use iodine, THEN the filter, THEN another charcoal filter like a Brita. They are also pretty expensive and I wanted to buy a backup. In the event Y2K blows over, my spare is going to be donated to missionaries in the Soviet Union, and I didnt want to go nuts with the expense.

Two friends have Pur. Great for virus protection, however there is no way to tell when the iodine matrix has lost its effectiveness. The filters are also paper which I have read is subject to tearing while filtering in some tests. In cold backpacking climates this can happen more frequently. They pump very hard compared to an MSR. Finally, I want to remove all chemicals from the water to avoid liver damage.

I spent about 30 minutes on the phone talking to MSRs Waterworks designer. There are a number of attractive features for the Mini/ Waterworks. - Screwtop adaptor so dirty particles are sealed off from the filter process. - Clear filter body. - Filter replacement gauge built into the body. - Ease of pumping! - Inner core of charcoal under the ceramic filter, to remore chemicals. - Miniworks is used by the US military after tests. - Entire filter can be disassembled. - The designer told me that although the packaging states filter to .02 micron, most particles are caught at .01 and they are doing more tests to make that claim. - The relatively inexpensive filter and cartridges ($30) might be used for barter. - MSR says that all filters are produced at one small plant in the US, and with current (hopefully compliant) technology. -Overpressure relief valve to avoid injection of contaminated water.

The disadvantage of the MSR is the number of parts, which can be lost during repair. The filters also only get about 150 gallons per. They also obviously require an iodine pre-treat to kill viruses. Ive used the filter in human excrement-exposed water (found out after filtering that some yuppies were crapping and peeing into the stream at a campsite up from us) with no ill results. My friend used his Pur during this incident and also had no aftereffects.

MSR makes dromendary bags which screw on the filters. They are black and heat up water pretty well, as this is a consideration in New England.

-- Tom (retro50@agapeis.net), July 06, 1999.

One thing I forgot to mention is the Pur self clean- you don't have to take it apart. The MSR requires some breakdown. Also, a Pur will not desalinate, as far as I know; Katadyn does make desalinators. They are in the $900-1500 range and produce water VERY slowly.

-- Tom (retro50@agapeis.net), July 06, 1999.

We got a Pure Water filter. From www.pwgazette.com/gravity.htm It is the exact same filter that is inside the Katadyne & Berkefeld. But just one portable filter, wheras they have big contraptions holding four. Hence the price difference. About $45. And the portabililty is a good feature. You could carry this in your coat pocket. The guy who answers the phone is very nice, too. Graciously takes the time to help you pick the best product for your situation. (Has with and without charcoal core, etc.) Yes, even if he makes a few less dollars. You just wipe the outside clean and it lasts and lasts. As long as your water is not full of visible gunk. Gravity flow, so no pumping at all. Shivani Arjuna

-- Shivani Arjuna (S Arjuna@aol.com), July 06, 1999.