No there is nothing you can do to prevent hermies, it all comes down to the genetics of each and every single plant. Unless all your plants are clones, there is no risk of the remaining plants going hermaphrodite due to just being in the same tent as the hermie plant; it is not transferrable or "catching".
If they were all grown from "bag seeds" the risk of hermaphroditism is greater, due to bag seeds being the product of hermied females, which will then become a dominant trait in any offspring. If your seeds are from a commercial breeder, the others should be ok, and to get the one hermie plant is purely bad luck.
Hope this helps,..... Organoman.