There are differences in the procedure between smoking cheese as compared to smoking fish or other meats.
To cold smoke salmon you either have to salt cure it, or use a combination of salt and nitrites - though using nitrites may alter the flavor of the fish. The salt and/or nitrites will stop or slow down the rate of growth of any pathogens that may be on the surface. Also the smoke has antimicrobial properties that help prevent the growth of bacteria.
This link gives some information on both hot and cold smoking salmon:Smoked Salmon
Keeping the cooking temperature below 85°F if very important, since fish proteins begin to cook at around 86°F. Though the link to the article below states that cold smoking fish, the temperature should stay below 80°F.Cold Smoking Nova Lox