Whether you’re involved in the packaging, shipping or handling of frozen foods, automotive parts or framed artwork with fragile glass contents, you may have been confronted with the need to specify corrugated graded by means of the Mullen Burst Test, or alternately, the Edge Crush Test (ECT).
The Mullen test measures a corrugated board’s stacking strength based on the pounds of pressure per square inch needed to burst the board being tested. ECT measures the straight compression force a sample board can withstand and work best in staking with self-supported loads, such as canned vegetables.
They’re similar, and indeed, there are equivalencies of grades between the two. For instance, Mullen 200# is generally equivalent to 32 ECT, Mullen 400# is equivalent to 61 ECT, and so on. However, ECT grades are not as strong as equivalent Mullen grades when it comes to side crush. Therefore, if you experience damage when shipping via such carriers as FedEx, UPS, or DHL, the first recommendation is to utilize a sturdier grade of corrugated and compare any damage to the initial grade. If damage continues at the same rate, we recommend consulting with an experienced packaging representative at PreferPack.
Traditionally, Mullen-tested boards had more virgin material with longer, interleaved fibers for greater top-to-bottom integrity. ECT-tested board typically had higher recycled content with shorter fibers, and carried cost benefits with some doubts regarding vertical compression. Today, reputable converters have since adopted process technology to align the orientation of shorter “ECT” fibers during manufacturing. Choosing one, the other, or a hybrid of the two, has become a bit more complex.
Three tips to make your next corrugated purchase a wise one…
Tip #1: Ensure that the corrugated you use, no matter the rating, is handled in conditions that follow industry guidelines with regard to humidity and other environmental conditions.
Tip #2: Train your personnel in proper packaging processes to protect the integrity of products in cases, and the strength of cases stacked in layers.
Tip #3: Choose experienced, reputable and knowledgeable suppliers to aid you in selecting the right material for your application — and the right price, not just today but for the long haul.
Need assistance? Explore our website to learn more about stock corrugated offerings and custom corrugated packaging, or a full range of corrugated formats. Or, call 877.284.7752 today to consult with a PreferPack representative.