Edge Crush Test (ECT)

It is measured by compressing a small segment of board on edge between two rigid platens or plates perpendicular to the direction of the flutes until a peak load is established. This is measured in pounds per lineal inch of load bearing edge (lb/in), but usually reported as an ECT value.  For example, 32 ECT is the value for standard strength of corrugated board, 44 ECT is the value for heavy duty, and 48 ECT is the value for heavy duty – double wall.

Edge Crush Test is a newer standard that has achieved widespread acceptance. Historically, the long time industry standard has been the Bursting (Mullen) Test, which is related to the rough handling durability of corrugated material. Bursting Test is a measure of the force required to rupture or puncture the face of corrugated board and is measured by a Mullen Tester.