Mullen test
The common name for the bursting-strength test of board, after the Mullen tester.
In practice
Boxes are sometimes graded by burst ("200 lb test") rather than by ECT. The two scales measure different things, so a conversion between them is a classification convention, not physics.
See it on Packgent
Related terms
- Bursting strength
- The pressure a sheet of board withstands before a rubber diaphragm pushes through it.
- Edge crush test (ECT)
- The load per inch of edge that a short column of board carries standing on its edge, flutes vertical.
- NMFC Item 222
- The rule in the National Motor Freight Classification that sets construction standards for fibreboard boxes shipped by LTL truck.
- Box maker's certificate
- A printed stamp, usually on a bottom flap, in which the box maker certifies that the box meets a carrier classification rule.
Definitions written by Packgent, last reviewed 2026-10-27. All terms.