Introduction
This is another interesting UV treatment system for rendering water safe for drinking. The UV radiation ‘kills’ or ‘disables’ all the viruses, bacteria and protozoa found in backcountry water. For that matter, as explained in our reviews of the original Steripen Adventurer in 2007, the Adventurer Opti in 2010 and the Classic3 in 2015, the UV method of water treatment is also used in local Council water treatment plants and by emergency services and the US Military. No tasty (or otherwise) chemicals, no filters to block up, no fuel for boiling, and it meets EPA requirements. What is not to like?
However, one of the interesting things about the whole Steripen wand system for the UV treatment of water is that the UV radiation goes from the wand, through a very short path in the water, to the wall of the container. Any UV photons which have not done their job in that very short path length are absorbed by the wall of the container and wasted. What a pity. Could on improve on the ‘photon efficiency’?
The Quantum system, photo by Steripen
This waste was noted by Steripen and they have come up with an ingenious enhancement. Instead of using a metal pot or a plastic bottle to hold the water, they offer a RapidUV Reservoir. You fill it through a funnel with 4 L of water (enough for 2 people for most of a day), insert the Steripen Quantum wand, press the go button, and 150 seconds later you have 4 L of drinking water. But the wand is pretty much the same as the Classic3, which takes 90 seconds for 1 L at the same power. That is, this Quantum system is more than twice as efficient. How do they do it? Simple: the inside of the Reservoir is highly reflective, so instead of wasting all those unused photons, they get reflected back and forth through the water. It’s all done with mirrors …
The Details
The UV wand looks identical to the Classic3 except for the colours and the timing/volumes. The Classic3 does 1/2 L and 1 L (90 s); the Quantum does 1 L (90 s in any container) and 4 L (150 s), although the 4 L setting requires the RapidUV reservoir (the 1 L setting does not). The water-sensing mechanism is identical (two metal prongs), and the 1 L performance is also the same. We will focus therefore on the 4 L aspect.
The unit comes with a solid but flexible plastic tag insert for the battery compartment. With it in place the batteries are all isolated. This is a wonderful idea: use it. After I removed the battery-isolating tag the first time I could not get the end cap back on. I could not see why. So I removed the batteries, replaced the batteries, and tried again – successfully. I suspect one of the batteries was not properly in its ‘slot’. Fortunately, when it works, it works easily. I did not have that problem again.
The RapidUV Reservoir, with water in it
The RapidUV reservoir is made of very heavy-gauge plastic with a big middle cap and a smaller cap on one side. It has a reflective inner lining to bounce the UV photons around. This gives the UV photons a far longer path through the water than you get with a metal pot or small bottle, which is why a single 150 second dose can treat all of 4 litres in one go. The reservoir is ‘robust’ – a bit heavier and bulkier than I had hoped for. The problem with going for something the weight of a Mylar hydrogen balloon (which would work just fine) is that it has to withstand mistreatment by the ‘average user’. A Mylar balloon would not; this reservoir should. You pay for the robustness. Incidentally, the RapidUV Reservoir can be bought separately: 2 for ~US$20.
The funnel with the Quantum in it, photo by Steripen
There is a two-part silicone rubber funnel to go with the Reservoir. Actually, the thin end will fit most any bottle, although only just for the 1.25 L rocket bottles. The middle part of the funnel drops into the big cap of the RapidUV reservoir easily: it does not clip in. I suspect this may be deliberate: make it a tight fit and you will spill water everywhere. The funnel is of course ‘squashable’. There is more: included is a small coarse mesh FitsAll filter which clips inside the funnel. ‘Coarse’ means it has no chance of stopping any bugs, but it is fine enough that it will stop most ‘floaties’. The wonderful part is that you can clean this filter just by blowing backwards through it, and it is not damaged by being squeezed or compressed.
The 1 L measuring cup
How do you measure out the 4 L of water into the Reservoir? Ah well, Steripen provide a collapsable 1 L ‘plastic bag’ with handles for this. It too is made of a stout plastic film, and the special folded bottom means it will sit upright on any flat surface. Very neat. However, one word of caution about the label on the bag. It says ‘(1 L)’ below a ‘Max Fill Line’, but that line is NOT the 1 L level. Only fill to just above the Steripen brand, as shown here.
The Reservoir, full of water, and bulging upwards
Now for the difficult part: pouring the water into the Reservoir. When empty the Reservoir sits flat – so one might expect that any water poured in will simply overflow. In anticipation of this my first test was done on the kitchen sink. I poured 1 L in. OK. So I poured a second litre in. OK. And a third, and a fourth. I did not have to hold the middle entry up in the air for this: the bag just swelled up all by itself, as shown here! That was unexpected. (Did they design it this way, or did it just happen? I don’t know.)
So I carefully removed the filter from the funnel – by first taking the funnel out, then I hit the Go button on the Quantum, and poked it into the funnel and put the funnel back in the Reservoir. The ergonomics here are much better than the original Adventurer: the Quantum is quite happy to be told to operate before it senses the water. It just waits until is is in the water before it starts. 150 seconds later the green LED flashed for success. And that was it. (There are 3 LEDs on the wand which do different things: a case of RTFM.)
Carrying a full bag around, pouring cap to left, photo by Steripen
So I removed the funnel and put the big cap back on. I could now pick the whole bag up by one of the handles. I undid the small cap (like on a rocket-base bottle) at one side and poured some treated water out. I replaced the cap and put the Reservoir down. Kind of easy.
The plastic around the big middle cap is labelled ‘Glow Ring’ (see 3rd photo). It does not glow – but the white threaded part in the middle does ‘sort of’. Certainly, you can see when the UV wand is on and when it is off.
Assessment
There is no doubt that UV treatment of water works and works well. There are no chemicals to worry about and no filters to block up – and not all filters handle viruses anyhow. The Steripen wands work well too, and the ergonomics on the current models are good. (There was a little battery hassle with the very first production batch of the Adventurer way back around 2007, but that is long past and gone.)
There have been complaints about the way the wands eat up batteries. Well, they do a bit, although using good lithiums rather than cheap alkalines solves 90% of that problem. (Most of the rest is solved by the battery isolator between trips.) The Quantum improves the battery situation: Steripen are claiming 78 full 4 L cycles from 1 set of lithiums: that is a lot of water. Provided you use the plastic battery isolator between trips, most users will be able to go for several years before they need to replace the batteries.
The Reservoir and its associated bits are a bit bulky, but you need them to get the 4 L treatment and the battery life. On the other hand, you could probably dispense with all your other water bottles and bladders, which significantly reduces the other bulk. I think the Reservoir is robust enough to be able to carry a litre or so of water in your pack. The only hassle I found with the Reservoir was that I had to be just a bit careful when taking the small cap off to avoid spilling, but that is not a major problem.
Technical Details
Weight of empty Quantum wand  83 g
Weight of 4 lithium batteries     ~141 g
Length of Quantum wand with cover    186 mm
Weight of funnel & filter                75 g
Weight of 1 L cup                         17 g
Weight of Reservoir bag             107 g
Size of entry port                          53 mm
Cost of complete system      ~US$70
