Explosive device right for underground worker (5)
I believe the answer is:
miner
'underground worker' is the definition.
(someone working underground in a mine)
'explosive device right' is the wordplay.
'explosive device' becomes 'mine' (mine is a kind of explosive device).
'right' becomes 'r' (abbreviation).
'mine'+'r'='MINER'
'for' is the link.
(Other definitions for miner that I've seen before include "Pit worker" , "One sent down for work" , "Digger for gold or coal, say" , "Collier" , "Coal worker" .)