Box Testing: ECT Test vs. Mullen Test

02 Mar Box Testing: ECT Test vs. Mullen Test

A common question we receive at Creative Packaging is what is the difference between the Edge Crush Test (or ECT) and Mullen (or burst) Test for boxes.  Do those tests tell you the same thing about box strength?  Think about it like the ACT and SAT, the tests aim to tell customers how strong and durable a particular box is but in different ways.  So at the end of the day, both the ECT and Mullen tests have the same objective, but their path of getting to that objective dissimilar.

The ECT Test measures the box board’s top-to-bottom compression strength.  This test looks at two areas of strength – Box Compression Stregth (BCT) and Stacking Strength.  If a customer is concerned about the maximum weight a box can stand, then ECT is your test.  Today, this is the most common type of test used (and the most common box sold is a 32 ECT).

The Mullen Test measures bursting strength of the corrugated linerboard (measured in psi).  Many customers like Mullen tested boxes for protection of heavier contents because they are concerned about the linerboard bursting.  While not as common today, many customers still prefer Mullen tested corrugated boxes (the most common Mullen tested box sold is 200#).

At the end of the day, both ECT and Mullen tested boxes come in a wide range of options.  Below is a helpful chart that shows an ECT tested box and its applicable Mullen tested box of similar strength.