If you are hunting a spot and the wind is taking your scent toward another stand, how far would the 2 stands have to be apart from each other not to spook deer at the second stand. 500 yards, 1000 yards or even further. Anyone have any experience with this.

I have stepped out of a shooting house with my wind blowing toward a field 400yds away with deer in it and about 30sec later they turned around and eased back out of the field the way they came in. They smelled me. They didnt blow and run out of the field. But they eased on out of there.

I hav caught them at 300 - 350 yards smelling me which is amazing and frustrating - not sure how far they can smell

Prob depends on the terrain some and how high up or not you are etc

I don’t think anyone can answer this accurately,
How long does human scent remain in air?

There are many variables in play. Thermals do different things in different times of day and different temps. As a rule, I’d say you’d be better off hunting that spot in the morning because thermals typically rise in the morning and fall in the afternoon. How hard is the wind blowing? Are you uphill or downhill from the spot? Lots to figure out, but if you’re 400 yards away I’d take may chances.

I've seen mule deer spook at 1000 yards

Depends on the human. Some be strong under the lip and the arm.

I know that guy.

Humidity plays a big role in scenting conditions as well.....there needs to be moisture in the air for scent to be easily picked up......the drier the air the tougher the scenting conditions