How close can marijuana plants be without pollination each other?

How close can you keep a single male marijuana plant to your female marijuana plants without inducing pollination? If you grow indoors, can they be kept in the same room?

As a general rule, marijuauna is fertilized by the wind. Pollen will float in the air and only a small percentage of it makes it to the female plant. Male plants produce incredibly large amounts of pollen to make sure pollination takes place.

If the marijuana plants are indoors, male plants will fertilize female plants that are kept in the same room. If the marijuana plants are outdoors, the pollen can end up floating through the air for miles. After about 500 feet, however, the pollen becomes too dispersed to produce many seeds. In essence, the rate of pollination is contingent upon airflows. Female plants that are upwind of the closest male plant might net produce any seeds.