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desiccantHow do we calculate the desiccant requirement for your Barrier Foil packaging requirements?
Many of our customers ask this question, wondering what method we use to make sure the right amount of desiccant is used for each individual barrier foil bag. Below is the calculation used for every application to make sure your contents arrive at their destination in pristine condition.
On every occasion we will always do the calculation for you but here you can see how we reach the required amount of desiccant we recommend for your specific order.

Desiccant Calculation –BRITISH STANDARDS BS1133-SECTION 19
For Temperate Climates: W=11ARM+DF
For Tropical Climates: W=40ARM+DF
W = Weight in grammes of basic desiccant
A = Area in square metres of the moisture vapour barrier
R = Water vapour transmission rate of the barrier in grammes 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 grammes of blocking, cushioning and any other hygroscopic packaging
D = Materials inside the barrier (including cartons etc.)
F = Factor, depending on type of dunnage

Our standard activated clay bags are 1 unit, 2 unit, 3 unit, 4 unit, 8 unit and 16 unit type approved to Mil-D-3464, Def Stan 81-68 and DIN 55473
If the answer to the formula is 400g of basic desiccant, then the customer would use a 16 unit bag of activated clay.


  1. Could you clarify the amount of dessicant required for a foil bag with dimensions of 144x122x122cms, no internal packaging will be inside the foil bag.
    Jackie Evans

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