Re statement "car parts".
You would be surprised, how many car parts are actually classified as "hazardous material", beginning with batteries, ending with air bags and seatbelt pretensioners (under certain conditions, they are classified as explosives Class 1.4 S as per MSDS or as Class 9, it depends on; have encountered a case like that where I advised my client to return this item to the shipper as it was not properly declared and there were more than just hazmat questions about this shipment). There are some interesting presentations by major automobile manufacturers showing the kind of hazardous material they are using in the manufacture of automobiles. And how do they get them?
Again, if a fibreboard box is wet/soaked, then the structural integrity of the box does not meet stated performance requirements, let it be a certificated hazmat box or a regular box. Consequences are easy to predict, especially for boxes containing hazmat. What else do we need? Any other holes of a Swiss cheese to be lined up, ending in the collaps of the Swiss cheese (translated: incident/accident)? Please advise.
Admittedly, the UPS 1 hour video is more than basic, but it contains key messages for the unload/preload personnel. The real mistake has been made well before it actually happens, and that is where incidents like the described one can be avoided at relatively minor costs.
FYI, in UK, a forwarder was sentenced to 12 months prison, because he was "convinced " by the shipper to not declare a hazmat shipment in the proper way due to "economic pressure". How often does this happen here in the USA?
Watch out for Li-ion batteries (primary and secondary).