What an end consumer should know about the level of IP protection provided for a vehicle against hazards which include but not limited to environmental factors, thermal runaway in batteries, etc.
Best open-access resources for EV electrical safety requirements are the American FMVSS 305:
and the European UNECE rule 100:
The requirements are quite similar and car makers usually design the vehicles to fill both the requirements. In the ISO and IEC standards are more accurate requirements, but the standards cost like couple of hundreds of dollars per standard (unless your university or company library has a mass license).
Following the standards is not mandatory but usually the easiest way to fulfill the legal requirements (FMVSS 305 and UNECE 100).