How do the heat packs work?

The heat packs contain sodium acetate (a salt), water and a metal disc. Sodium acetate has a freezing temperature of 100-120F, and are "supercooled", so that theystay in their liquid form below freezing temperature. Once the disc is clicked, a reaction causes the sodium acetate to heat up and "freeze".

By boiling the heat packs for 5-15 minutes, it re-liquifies the sodium acetate, allowing it to be used again, making it a re-usable heat pack.
More explanation of the sodium acetate reusable heat packs can be found here.

I put my heat packs in hot water but every time I take the pack out it solidifies again! What can I do?

As explained here, sodium acetate heats up and solidifies again when they have something to crystalize against, so when boiling the pack, you have to make sure you do it until there are no crystals left.

My reusable heat packs only last 20 minutes! What can I do?

The reusable heat packs last longer when insulated, so once activated they should immediatley be put in the glove. If you soften the sodium acetate while it solidifies it will also last for longer. Testing showed that while insulated, the reusable heat packs can last for over 2 hours.

Are there any side affects? Is it safe? I swallowed some of the liquid; will I become radioactive?

Sodium acetate is a food grade salt. In fact, it is the same kind of salt that is fond in vinegar! So it is absolutley safe, even when ingested.

How long is the life-span of one of the reusable heat packs?

Theoretically, these heat packs can be used an infinite number of times; hence the term re-usable heat pack. However, there is a chance of getting some wear and tear on the plastic bags. If there is a break or a leak in the pack, please discontinue use. You can buy more of the reusable heat packs at our company store.

I have more questions that aren't on the FAQ! Help me!

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