Box Strength & Burst Ratings (ECT vs Mullen) vs. Corrugated Cardboard Flute Profiles
Comparing 2 standards across 13 specifications. 13 key differences identified.
Corrugated cardboard shipping boxes are legally rated under two distinct testing standards stamped inside the Box Maker's Certificate (BMC): the Edge Crush Test (ECT, measuring top-to-bottom compression stacking strength in lbs/in) and the Mullen Bursting Test (measuring puncture resistance and rough handling in lbs/sq in).
Corrugated fiberboard packaging is engineered by sandwiching a wave-shaped arched paper medium ('fluting') between flat linerboards. Standardized into letter designations (A, B, C, E, F), flute profiles define the physical caliper thickness, flutes per linear foot, and the balance between stacking crush strength and high-resolution printability.
Specification Comparison Table
13 Parameters| Parameter / Spec | ||
|---|---|---|
|
Governing Standards
|
TAPPI T 811 / TAPPI T 810 / ASTM D2808 / NMFC Item 222 (National Motor Freight) | FEPA (European Corrugated Federation) / TAPPI / ASTM D4727 |
|
Edge Crush Test (ECT)
|
Measures compressive edgewise strength (lbs/linear inch) parallel to fluting — predicts pallet stacking capacity | — |
|
Mullen Bursting Strength
|
Measures hydraulic pressure (psi / lbs per sq inch) required to rupture the linerboard face — predicts puncture survival | — |
|
Standard Single-Wall 32 ECT
|
Equivalent to 200# Burst | Max Gross Weight: 65 lbs (29.5 kg) | Max Total Dimensions (L+W+D): 75 inches (190 cm) | — |
|
Heavy-Duty 44 ECT
|
Equivalent to 275# Burst | Max Gross Weight: 95 lbs (43.1 kg) | Max Total Dimensions: 95 inches (241 cm) | — |
|
Double-Wall 48 ECT
|
Equivalent to 275# Double-Wall | Max Gross Weight: 100 lbs (45.4 kg) | Max Dimensions: 100 inches (254 cm) | — |
|
Double-Wall 51 ECT
|
Equivalent to 350# Double-Wall | Max Gross Weight: 120 lbs (54.4 kg) | Max Dimensions: 105 inches (267 cm) | — |
|
A-Flute (Original)
|
— | Thickness: 4.8 mm (3/16") | 33 ± 3 flutes/ft | Maximum vertical cushioning and top-to-bottom compression |
|
B-Flute (Puncture Resistant)
|
— | Thickness: 3.2 mm (1/8") | 47 ± 3 flutes/ft | Superior puncture resistance and die-cut foldability (canned goods) |
|
C-Flute (Universal Standard)
|
— | Thickness: 4.0 mm (5/32") | 39 ± 3 flutes/ft | Dominates ~80% of all standard RSC shipping boxes |
|
E-Flute (Micro-Flute / Retail)
|
— | Thickness: 1.6 mm (1/16") | 90 ± 4 flutes/ft | Excellent smooth crush-resistant printing surface for retail cartons |
|
F-Flute (Ultra-Thin / Folding)
|
— | Thickness: 0.8 mm (1/32") | 125 ± 5 flutes/ft | High-end cosmetics, fast-food clamshells, direct litho printing |
|
BC-Flute (Double-Wall Heavy)
|
— | Thickness: 6.8 mm (1/4") | Combination B + C flute for heavy appliances, furniture, and master shippers |