SteriPEN and other water purifiers

In My Humble Opinion
1

Hi folks. I’m looking for a lightweight water purifer to use primarily with municipal water in countries where tourists are not supposed to drink untreated water. The SteriPEN water purifiers would certainly be convenient, especially the one with a solar charger, since I’ll need to travel light and also don’t want to contribute spent batteries to the trash (which gets burned or buried). The ad copy describes this product as effective and independently tested:

Most reviewers on the REI site seem to think it’s useful for my purposes. I also plan to carry backup rechargeable batteries, some coffee filters for straining if needed, water purification tabs, and a course of Zithromax. The alternative is buying something like a Katadyn water filter or a MSR MIOX purifier.

While I’m not interested in taking risks, I’ll add that I’ve had the Hepatitis A/B vaccination series and I’m in mid-series with the Ty21a attenuated Salmonella typhi live oral vaccine.

My questions:

Is there any health/sanitation advantage to one method over the other (UV vs. filtration)?

What have your experiences been with different water filtration methods under the circumstances I describe?

Is there anything else I should be thinking about as I continue to refine my work-in-poor-countries kit?

Thanks.

2

The most important detail to consider regarding the UV method is that it will only work properly on “clear” water. If there are particulates (the water appears cloudy or colored), the UV will not be able to penetrate and may not completely disinfect the water. Since you are dealing with a municipal system this presumably won’t be a huge issue. I might take along some chlorine tablets as a backup, just in case.

If I were traveling for long periods of time, I would probably choose the physical filter over the other two methods because the technology is simple and sturdy, and it’s easy to verify that the unit is working. They all look pretty straightforward and reliable, though.

Per the spec, it would take the MIOX 4 hours to disinfect for crypto, which might not be convenient.

Bottled water could also be an option. Sometimes vendors refill used water bottles, so make sure you check the seal before buying. Also ask for all of your drinks without ice.

3

Thank you! (I have yet to have problems, due to precisely the combination of checking seals, no ice, judicious choices of fruits and vegetables, not eating street food, and boiling the water, but I have some travel coming up that includes eating in people’s homes, so I’m trying to plan ahead.)

4

(I didn’t get this posted when it was mostly done, too many fireworks to [del]set off[/del] watch, so it reiterates what Barrett Bonden already posted :smack:.)

Filters are just that filters, you can stick the draw tube in a mud puddle and get safe, clean water out the other end. You can’t do that with the UV units, the water has got to be clean enough for the UV to “see” the nasties. Not much of a problem for your planed use, but what if there’s no “clean” water when you need some?

The UV’s don’t make much safe water per use, the MIOX takes a really long time to work (4 hours for cryptosporidia :(), you’ve got to know way ahead of time how much water your gonna want. Filters give you as much water as you want, when you want it.

The battery powered units are useless if they ain’t got charged batteries, as long as you’ve got arms you can pump a filter. Filters are pretty much bomb-proof and easy to clean. For your intended use a ceramic filter, NOT an iodine matrix one, will last for many, many, years (still a good idea to get a replacement filter cartridge, just in case, they can break if they’re dropped).

IF you go with a battery powered unit, I’d go for one that can use AA/AAA NiMHs, CR123’s can be hard to find here.

Yeah, that whole battery thing. I’m betting ya got some other AA/AAA powered [del]toys[/del] gear; MP3 player, camera, flashlight (you do have a good AA/AAA, multi bulb, LED flashlight, right? And a headlamp?), etc.

I’d get a really small electric charger for AA/AAAs (there’s a couple from the major battery companies that fit in the palm of your hand) and a solar one that charges at least 4 batteries. Solar is nice, but if the conditions ain’t right, it can take days to charge a set of batteries. Get the biggest solar panel size you can find, bigger panel means better output from the available light. Look for a flexible one, easier to pack.

Get NiMHs (NOT NiCADs!) with the highest mAh number you can find.

One set of the low self discharge/long shelf life ones, one set being, the number of batteries for the thing you have that takes the most batteries x2 (most likely 8). All rechargeable non-lithium batteries will go dead after a couple of months, the lsd/lsl ones hold a charge for up to a year. There are rechargeable alkalines but in my experience they ain’t worth the trouble, they didn’t hold a charge and they leak! These are your emergency batteries.

One set of regular NiMHs, one set being, the total number of batteries for everything, plus batteries for the thing you have that takes the most batteries x2.

One set for each recharger. That way you don’t have to wait for dead batteries to recharge you’ve always got a freshly charged set ready to go.

And lithiums, one set, (one set being, the number of batteries for the thing you have that takes the most batteries x2 (most likely 8). Regular old alkaline batteries will also go dead in storage, lithiums don’t. That LED flashlight you have shouldn’t have anything but lithiums in it, if you need a light you NEED a light, not a battery change! These are your super emergency batteries that you know will work when you need them.

Now that might sound like way too many batteries, but think of it this way. Ya really want to do the battery shuffle, take 'em out of the MP3 player to put 'em in the camera so you can take those once in a lifetime pics … only to discover that they didn’t have enough juice left to take a couple of pics? And don’t let the sticker shock get ya either, 4 NiMHs for ~$10 is ~4,000 batteries, 40 AAs for $10 is a steal! 4,000 is :cool:!

CMC +fnord!

5

I discovered an interesting way to test the Steri-Pen (Yes, I have one, as I like gadgets)

I discovered that the water in a fully cycled aquarium has a faintly greenish cast when illuminated by near-UV light (385nM), I have a Minimag with a UV LED in it, so I drew a glass of water from my cycled aquarium, shined the UV through it, confirming the existence of the Nitrosomonas and Nitrobacter nitrifying bacteria (green cast)

I then dosed the glass of water with a single dose from the Steri-Pen, and then checked with the UV Minimag again, the water took on a much grayer cast, clearly a large number of Nitrifying bacteria had been destroyed, a second dose of Steri-Pen UV exposure made the water take on a even greater gray color cast

by comparison, water drawn directly from the faucet had no color cast