Controlling urge to masturbate

Hi, 

I spent a while trying to work out what to sensitively call this subject…. My son is 16 yrs old and has become quite obsessive about masturbating. At home he understands that his bedroom is his private place, the difficulties arise when on holiday. With less private space in an apartment etc…. he becomes ‘possessed’ with a need to masturbate.  This ends in huge meltdowns. Does anyone have any advice on how to help him control the urge….. ? We currently are unable to go away with him.