The latter suggests you device must be able to withstand an explosion. But the current header might attract more attention :-) According to the title, you could design a device that would cause explosions and fullfil the requirements, as long as it survives them.
As described above, the explosion proof motor enclosure is constructed will all the right clearance, thickness and components so as to withstand the explosion pressure with the prescribed factor of safety. This makes the overall construction very robust.
As motors operate at high voltage, explosion proof is the only protection mechanism, not intrinsic safety. Intrinsic safety allows the use of conventional instrumentation cables to wire from the safe area to the hazardous area.
From a basic design standpoint, an XP device must be able to withstand an explosion within its enclosure. As briefly described above, escaping gas must be allowed to cool as it expands and passes through the flame paths from inside the enclosure to the outside environment.
Normally an explosion proof container is a rugged sand-cast aluminum case design to withstand high pressures. Better products use an epoxy coating. So moisture sealed alone is not adequate to prevent any possible explosion from an electronic failure.
Explosion proof/intrinsic safety are two technologies which guarantee that under no circumstances will equipment emit energy to cause an explosion. The objective of this document is to describe how to do the mechanical and electronic design for electrical/electronic equipment deployed in a hazardous environment.