<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by Middle_Seat:
Isn't 100 proof the dividing line between flammable and non-flammable booze? This could be a rationale for permitting the lower-proof varieties.
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You are absolutely correct that the ban on higher proof alcohol is a safety issue. These bans hold for both carry on and checked luggage. You wouldn't want the pax next to you carrying a bottle of gasoline on the plane, would you?