Canon A-1 - Manual (Page 170)

is necessary, do not attempt to do it yourself
but take it to an authorized Canon service
facility. The film compartment also requires
occasional cleaning with a blower brush to
remove accumulated film dust particles
which might scratch the film. When doing
this, take special care NEVER to exert
pressure on the shutter, the rail surfaces or
the pressure plate.
Salt and sand are your camera’s worst
enemiés. .\fter using it on a beach, clean it
thoroughly. If you accidentally drop it in
the water, it may be irreparable but take it
immediately to an authorized Canon service
facility.
-9