The Swiss franc gained against the euro, boosted by investors seeking a safe haven for their money as a fire at a reactor damaged by the Japan quake stoked fears about the disaster's effects on the world economy. The franc was up 0.6 percent against the euro compared to the New York close, trading at 1.285 per euro at 0823 GMT. The franc 0.2 percent stronger against the dollar at 0.9225 per dollar.