This is correct but be sure to let the enclosure and bedding or paper completely air dry for awhile. A half hour to be safe. I also wouldn't treat every 2 weeks. There was a study done on household lice sprays and they retain their residual effect just as long if not longer than P.A.M. so I'd wait 3-4 weeks before a second treatment.
Keep in mind that permethrin is a dangerous chemical. Whether its in the P.A.M. on in lice spray, it needs to be used carefully and only as much as needed. A little goes a long way. Never put it directly on the snake.