My company makes dozens of pallets each day so I thought I would clear the air in regard to new pallets in the U.S.
Step 1: NPPO/IPPC Standars
Pallets now require an IPPC logo which certifies that the pallet was heat-treated or fumigated with Methyl Bromide.
The standard is a 2 letter country code (xx), a unique number (000) assigned by the National Plant Protection Organization (NPPO), HT for Heat Treatment or MB for Methyl Bromide, and DB to signify debarked.
The logo in the first image shows that it was produced in the U.S., the material was provided by 11187 (Unique number assigned to the producer), it was heat treated (HT) and was verified by PRL (Package Research Laboratory)