3 Ways to Compare Performance of Insulated Boxes
If you are shipping temperature sensitive goods in an insulated box, you’re putting a lot of faith in the insulation. When choosing your insulation, you might be tempted to just bring in samples of every kind of insulated box, fill them with your goods, and ship them to test customers across the country, just to see if your good survived. But before you do all that, wait!
So that you’re not wasting goods or, even worse, potentially losing face with customers, you can easily narrow your choice down to the products that work best. Here are 3 easy ways to test box insulations side-by-side and see which ones perform best.
1. Let Us Test It For You - Free
The simplest solution is to send your current insulated box, or other types of insulation you'd like to test, to us. We’ll be happy to test the R-value (insulation performance) and compare it to other solutions you’re considering. We offer this service absolutely free of charge.
Using a version of a test known as the Burgess Method, we maintain a cold internal temperature within the box and measure the heat absorption over 24 or 48 hours. From this information we are able to calculate an exact R-value of each insulation system and give you a report on how they compare to each other.
2. Send It Out for Paid Testing
If you need your box performance certified by an accredited lab, there are several commercial testing facilities across the country that can perform a temperature profile test. The industry standard test profile is ISTA 7E, performed in conjunction with Standard 20. This testing standard uses an environmental chamber to simulate real-world temperature variations across different climates and seasons to see how your payload holds up.
The ISTA test is meant to simulate the shipping of an insulated box with payload, taking into account things like climate and seasonality. That being said, this test my be overkill (and overly expensive) if all you need to know is how different insulation systems compare relative to each other.
3. Test It Yourself
Even if you don’t have your own environmental chamber, you can still test the relative performance of different insulated boxes and compare them to each other. The test is surprisingly easy! Here’s how you do it:
What You’ll Need:
2 or more insulated boxes with the same internal dimensions (i.e. the final dimensions of the payload area, after inserting the insulation, need to be the same for all containers being tested)
1 box of resealable freezer bags - 1 gallon size works well
Ice (preferably bagged ice purchased at the store) – enough to completely fill the insulated boxes
1 strainer – a pasta strainer will work fine
1 small scale - sensitive enough to measure from 1 oz up to 10 lbs
1 large bowl or bucket
Pencil and paper
Directions:
Step 1: Leave the ice out at room temperature for at least 1 hour to begin to melt, just enough to where the ice is wet (this ensures that all the ice is at 32F).
Step 2: Using the strainer, fill the resealable bags with ice, not water, and weigh each bag to ensure all bags have the same weight of ice. Seal the bags tightly. Double-bag if necessary to prevent leaks.
Step 3: Load the bags of ice into the insulated boxes, ensuring that the same number of bags and same weight of ice goes into each box. If possible, you should minimize the amount of open head space left in the boxes.
Step 4: Seal the insulated boxes and leave them out, side-by-side but not touching, in the same environment. (Room temperature is fine since we’re only testing the boxes in comparison to each other.)
Step 5: After 24 hours, open the first box. Strain off the water and dump the ice into the large bowl. Weigh the ice left and write down the weight.
Step 6: Continue the same procedure for each box, noting the weight of ice remaining in each. (If after 24 hours any box has no ice remaining, the test is invalid and must be repeated for a shorter time frame).
By comparing how much ice is left in each box - the more the ice remaining, the better the insulation - you’ll know exactly how the insulations compare. While this test method won’t give you exact R-values or meet FTC, ASTM or ISTA requirements, it is something quick and easy that you can do yourself just to get an idea of how one insulated box compares to another.