Some people wish to make items from pallets, but there are certain marks which denote treatment stamps on old pallets that you need to be aware of:-
HT. = Heat treated. This pallet has been heat treated to eliminate parasites and insects.
KD = Kiln Dried These pallets have been heated in a kiln to kill off any wood pests. Kiln drying also eliminates fungal growth.
MB. = Methyl Bromide. These pallets have been treated with highly toxic pesticide .You should never use pallets for craftwork and you should never burn these or put into a wood burner.
Lastly do not use pallets stained bright colours as they usually belong to rental companies and you can be fined by that company if you use them for your projects.