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Old 01-25-2013, 02:57 PM
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Quote:
Originally Posted by davej View Post
Something else to consider is that the heat packs need a supply of oxygen for the chemical reaction to take place and create said heat. I the box is air tight the oxygen will get used up heat producing reaction will stop.
Hmm interesting, maybe suppliers should start drilling some air holes in their boxes
The amount of O2 needed is minuscule at best, boxes should be sealed air tight, allowing air in would be quite foolish and counterproductive.