Two separate questions.



Should the water purification tablet be kept in their foil pack, or would take them out and repack work? Given how small they are repack would reduce the overall size by quite a bit.



Also I see a lot of PSK, ready made and otherwise, have scalpel blade in them instead of single edged razor blade? Any specific reasons? In AMK PSK it even claims to be more functional. Scalpel is sterile as in foil pack but I really don't see any need unless one perform surgery on himself, and I'm definitely too chicken to do that. Single edged razor is much easier and more comfortable to hold onto and safer to use, since it's made to be hand held instead of attached to a handle.

I always keep the tablets in the foil package. A pack of 50 does not take up that much room and the benefits of factory packaging in terms of shelflife are significant.

I guess that's what I'm wondering about, does repack reduce shelf life?

I pondered that very issue in an essay I wrote about the PSK in my blog. I did not really come to any conclusions, despite writing two whole paragraphs about it.

http://ilbob.blogspot.com/2010/02/mini-survival-kit.html

Logic behind the scalpel blade is that it can be lashed to a small branch to make a serviceable light duty knife. Unlike a single edged razor blade. It also has a point on it. Makes it very handy for getting a foreign object out of yourself.

Speaking as someone who has been there and done that, it is often easier to remove something like a splinter by cutting the skin over it. This has a couple of advantages i.e.: You don't do more damage trying to drag it back out the way it came and the wound can be more easily cleaned. Preventing septicemia or tetanus is something of a priority in a survival situation.

I duno, the corner on a fresh razor is pretty sharp too. Plus it has two notches on the side and a hole in the middle, which could be lashed to a stick easier than scalpel I think.

I am not sure about the scalpel blade.
I do have a couple of ideas though.

I think the big reason is the foil packaging and that it is very small. Any single edge blades I ran across were only protected by a cardboard folded around them or came in plastic boxes. They soon worked loose from the card and then I had a loose razor blade on me, and the plastic cases were too bulky.
The scalpel blades stayed safe in the package.

Another point is I can get scalpel blades in high grade stainless steel, which means they don't rust like the razor blades I tried did. Rust is one of the reasons that exacto blades don't work well in a survival kit either.

About utility I tend to agree with the comment that they are awkward.
I found the best improvised handles were plastic. If you heat the plastic up until it is melting and press the scalpel blade into it you can get a fairly solid connection.
Toothbrush handles or even a plastic pen will work.
(I really do not expect to be doing surgery or cutting down trees with them.)

I only have #11 scalpel blades in my FAK, and the only reason they are there is for lancing boils, digging out splinters, and stuff like that.