Heat Pack Experiment

We frequently employ heat packs to keep our boas warm when we ship them. These heat packs will generally tell you their maximum temperature and how long they will sustain heat. However, I was curious as to how much they would actually change the surrounding temperature within the shipping box. With some tools I have available in my chemistry lab at school, I was able to set up a simple test. I used a small box with styrofoam inserts for the test. This box size would be typically used for a baby boa. I inserted a computer controlled temperature probe into the box together with a 40 hour heat pack. The probe took temperature readings every 3 seconds and the data was automatically graphed over time. The ambient temperature remained relatively constant in my lab. The box was empty. I wish I had stuffed it with newspaper to better simulate shipping conditions.

What I found was that the temperature was increased by a maximum of 4.5 degrees Celcius after about 5 hours. I was surprised by this result. I thought that there would be a greater temperature increase. One premise that motivated me to conduct this experiment was that I thought we were overheating these boas with all these heat packs that were being used. I thought the animals were in danger of overheating because they lack a method to dissipate heat such as sweating or panting. This was just one experiment, but it did affect my attitude towards heat packs and how I use them.

The temperature probe connected to a computer interface system.

A broader view allows you to see the whole set-up.

A standard sized shipping box for small boas.

The heat pack that was used in the experiment.

The styrofoam was not "single unit" but 6 inserts (with two small holes in each side).

The black tip would be the location of the temperature measurements within the box.

The heat pack was attached to the top insert.

The box was sealed to simulate shipping and measurements were begun.

This is a graph that charts the measured temperature in degrees Celcius versus time in hours.

My next experiment is to take blood samples from all the different subspecies and "morphs" of boas and sequence their DNA to determine what really makes them different. Well, at least I can dream.