Bring the Boom

Spells like fireball and burning hands make the distinction that only bits of paper and kindling you’re not holding burst into flames from the spell’s effect and that anything you’re holding is immune to the ravages of purifying fire. It also means your clothes are also immune, and you’re not going to be rendered naked by a few untimely¬†flaming spheres. Modesty is retained!

Now, of course, this is to prevent characters catching fire and taking ongoing damage and slowly being burned alive. Or something valuable, like a wizard’s spellbook, being destroyed.