Rash, one caused by such a fire? (9)
I believe the answer is:
unguarded
'rash' is the definition.
'one caused by such a fire?' is the wordplay.
I cannot really see how this works, but
'one' could be 'un' (I've seen this in other clues) and 'un' is present in the answer.
'a' is found in the answer.
This explanation may well be incorrect...
(Other definitions for unguarded that I've seen before include "Not protected" , "like man liable to be taken on board" , "Imprudent" , "Open to attack" .)