RB800 external fan's

I am putting 2 rb800’s and 2 Rb600’s in an outdoor enclosure along with a small poe switch. I’m concerned about heat. Could I damage the rb800’s if I use 12V fans on the 5.5v jumpers?

Thanks

can you show us data of the enclosure please? I need a “big” outdoor box too.

does the rb800 can hold an external 12v 0.2a external fan???