why would it be a concern ---if all is working correctly is good ..if not--is a moot point...seriously--i havent found any problem even when things didnt work correctly--lol---wont boom, if that is what you are concerned about....and generally the ob and bbq are on differing areas of transom......had a cal 25 in 1999--lol----small area for all the goodies...and had a open transomj for engine, so bbq had to be on a corner of the rail...i usually place my railmunted ones on the corner of the sternrail....or just slightly forward of the corner....works well and there in less exhaust smell near the cooking area/......