Function and life cycle of a Heat Pack.
How does a heat pack create warmth?
After some reflection I couldn't stop marveling at how whimsical and kid like that very question made me feel. As adults it's clear that ultimately a product of this nature is very much about function. Whether that is staying warm during the harsh weather of a hunt, keeping you comfortable in the bleachers cheering on your favorite sports team, or even stabilizing the temperature for shipping out live product in the mail. It's clear from an adult's perspective when we open a heat pack we aren't necessarily concerned with how it generates heat, but that it creates that heat quickly and reliably.
On the other hand, from a child's perspective a heat pack must indeed be a tiny miracle. You open this plastic sleeve and out comes a pouch that spontaneously brings warmth delivered on demand. I can only imagine that every child hesitates and day dreams about what could possibly be going on in that pouch.
That said, it's not magic! What many wouldn't expect is the desired effect of heat is simply the by-product of a chemical reaction taking place safely within the pouch.
As described in the diagram above the heat we feel is generated by an oxidation process. Better known as rusting. Iron powder tucked within the pouch begins to rust once the plastic sleeve is torn and the pouch is exposed to air. Oxygen in the air is the last component required to complete the chemical reaction. Once exposed to oxygen the process will continue as long as there is fuel to keep the oxidization process going.
You'll notice different duration lengths available. These duration lengths correspond to how much fuel is contained within the pouch. Thus, longer duration heat packs will also weigh more on a per pack basis.
Choosing heat packs for one's application is straight forward. Simply choose the duration that best fits your needs and start testing. Testing is an important step to ensure you do your best to obtain repeatable and safe results when shipping perishable product. We encourage folks to do as much testing as is required to establish a reliable method for shipping that reduces the risk for loss.
HeatPacks.com does not assume responsibility for the misuse of our products. Any damages that occur from misuse or customer negligence are their sole responsibility.
We do not ascertain that our products will guarantee successful delivery. We do know that using our products properly will help ensure you the best chance of successful delivery.
- Marshall Joas