Heat Treated & Kiln Dried Pallets
Some pesky uncle may have heard something about pallets being unsafe. #fakenews. They are safe.
Are pallets safe? Yes. If they've all been Kiln Dried or Heat Treated. If the stamp says MB - leave it be. That's the short answer. For a longer take on HT vs KD read this from the Herwood Pallets, Inc. http://www.hwppallets.com
Think complete sterilization! The goal in heat treatment is to completely eradicate any and all living organisms in the wood. This process is similar to pasteurization in other industries. The lumber used to construct crates and pallets must be thoroughly heated to reach an internal core temperature of 132.8f for 30 minutes. Lumber that has undergone heat treatment can sometimes appear darker, or look worn or older. It’s not! The sap inside the lumber reacts to the heat process, creating a darkened stained appearance. It’s important to note that heat treated lumber weighs less and is stronger.
Kiln drying is used to reduce the moisture content of wood. Lumber is stacked inside large heating rooms (kilns), and then heated to evaporate excess moisture. It is more of a curing process and the goal is to prevent excessive warping of sawn lumber, and to reduce the weight. Kiln drying processes can vary, but the goal is not sterilization, so often the internal temperatures are not high enough for long enough periods of time to effectively sterilize the lumber.
If you need even MORE information, check out the The Canadian Wood Pallet and Container Association's FAQ document details on HT ISPM 15.