By safe, I mean not dangerous to human life and will not damage the carpeting or upholstery.

Most of the mildewcides you see are prescribed for "hard" surfaces, like tile, etc.

The car could air out for at least six months or so, it wouldn't need to be drivable right away.

So I could spray the car, leave it closed up for a while (weeks?) while the mildew was killed, then air it out for a lengthy period.

Any suggestions?

Thanks.

Jack