by Stephanie Warwick Stephanie Warwick No Comments

At Protective Packaging, we get lots of enquiries for foil bags, desiccant, and enquiries for foil bags with desiccant pre-fitted into the seal of the bag (Pro-Gel).

Failing to use the correct amount of desiccant can cause moisture damage to your goods during transit or storage. In order for us to ensure that your goods will be protected we religiously use the below calculation to decipher the amount of desiccant you actually require for the length of time your product will be hermetically sealed inside a foil bag.


For Temperate Climates: W=11ARM+DF
For Tropical Climates: W=40ARM+DF

W = Weight in grams of basic desiccant
A = Area in square metres of the moisture vapour barrier
R = Water vapour transmission rate of the barrier in grams per square metre per 24 hours, measured at 90%RH and 38°C (100°F)
M = Maximum time in months of transit and storage
D = Weight in grams of blocking, cushioning and any other hygroscopic packaging
D = Materials inside the barrier (including cartons etc)
F = Factor, depending on type of dunnage
If you have any questions or need advice regarding foil bags or desiccant, or both, feel free to get in touch on 0161 976 2006 and we will be happy to help.

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