November 4, 2016

Crayon Brands Heat Stress Test

There's a great verity of prices of crayons, especially at back to school sale time from fifty cents to a penny.  So many to choose!  We want to send nice things to the children in our boxes, but we don't want to spend money just to get a name.  So I decided to do some tests.

We tested five brands for both coloring quality and resistance to heat (that they might experience in transit).  The brands we tested were Crayola which you can normally get for $0.50 at Walmart & Dollar General during back to school sales.  Cra-Z-Art are normally $0.25 during back-to-school sales at Walmart.  Playskool can be found at Dollar Tree and other dollar stores for $1.  Dollar General offers a brand I*Magine often 3 for $1 or $0.33/$0.34 a piece at Back-to-school.  Also at Office Depot I got some Scholastic brand for $0.01.   All those prices are for 24 count except Playskool that is 36.  For those who are concerned about manufacture location:  most are made in China, Crayola is made in the USA or Mexico, you'll have to check the package.

First, how do they color?
You can see images and thoughts of our coloring test post here: Crayon Brands Coloring Test

Second, how do they hold up to heat?

My understanding is that Australia & New Zealand have had so many problems with crayons melting, they've added them to the "do no send" list.  Now, their collection is in the summer as they're in the Southern Hemisphere, they have more extreme heat, and I've heard reports from those on distributions in Africa from the USA reporting the crayons came through fine.  But, still something to consider.

So, we decided to do some heat stress tests.  These were all conducted in the South Eastern United States in August, so pretty hot!  So, high temps in the mid to high 80's (degrees Fahrenheit).  We did multiple tests, and here are the results.  All were in place for a week, except the the one in the windshield that within a day was so clear I stopped it before it made a mess!

To be totally scientific, here's the control-all intact at room temperature, so 70-80 degrees:

Then we put one in the garage, so consistently high temperatures (80-90 degrees I'd say):

One went in the attic (I'm guessing 100ish degrees):

One went in a car trunk that was driven to work daily, and sat in the sun, temperatures should be 5-10 degrees less than in the body of the car/van, so let's say 110-125 degrees (Source:  Jan Null, CCM, Department of Meteorology and Climate Science, San Jose State University, )

Then two went in our minivan.  One in a box in the back, so not in direct sun, but the van was consistently in the sun, so the temperatures should have reached around 135 degrees according to this chart I found (  You can see many of them lost their shape, and most oozed grease.  CraZArt held up best.

The others went right in the sun, and if they were dark, studies have show that could reach 200 degrees, even being lighter, they could have gotten excessively hot!   (Source:  Jan Null, CCM, Department of Meteorology and Climate Science, San Jose State University, ) You can see some of them are even liquid!  My biggest surprise was Crayola didn't do well!!  Once again CraZArt was the best with heat.

The question then becomes, how hot might the crayons get in transit?  According to one study I saw ( in the South Western US, the internal temperature of trailers was measured, some did peak at around 140 degrees, but most reached 120 at the most.

A study of containers shipped from Japan (, one route of which crosses the Equator and goes past many shoebox recipient countries showed a highest recorded temperature of 135 degrees.

So, that's the information I could come up with of how different brands of crayons react to different temperatures, and what temperatures they might reach on their journey.  I hope it helps people decide which kind they wish to send in their boxes.  It has changed how I look at it, and I certainly will be bagging all of my crayons in case any do melt/ooze grease!

Happy Packing!


KayM said...

Thanks so much!

tsirois1 said...

Good to know, I bought a bunch of Crazy Art crayons at the end of back to school when our AHG troop decided to pack for OPC. I was wondering if they would hold up as well as Crayola and I am happy to see they did, if not better!

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