Fire Testing For Safest Foam Board Insulation

Buzzcut1 wrote:
if I was planning on sealing gaps in areas where I was worried about fire I would use a fire resistant expanding foam that is certified for just that purpose. There are many of them commercially available with ASTM certification

I've used the Great Stuff Orange fire seal foam for a lot of penetrations for plumbing and electrical, also for framing fire blocking. Beware though, the fire block foam expands a lot and can have expansive force behind it that could be tricky to control in the thin wall space of truck camper walls.