ISPM15
In order to comply with ISPM15 (International Standards for Phytosanitary measures) we have been using heat treated pallets since a number of years. The ISPM15 guideline can be found here.
Details of the "Wheat Stamp" are:
Registration number NL - 076 HT DB - marked on each pallet
Temperature > 56 ºC in the core for at least 30 minutes
Kind of timber white wood
Technical insulation