Questions that deal with inflation (5)
I believe the answer is:
pumps
I believe this clue is a double definition.
'questions' is the first definition.
(as in to pump someone for information)
'that deal with inflation' is the second definition.
(items which inflate things)
(Other definitions for pumps that I've seen before include "Water-raising devices" , "footwear" , "Forces liquid to move; light shoes" , "Light dancing shoes - force air into" , "Plimsolls" .)