Manufacturer's directions probably.

wait...you need a permit and inspection for a 'dropped' ceiling....good greif.

"My zone is: North East"

That says it all.

Actually they are just recently requiring the hangers here in the northeast, they have been required in Florida for about 10 years.

Here is a photo of the hangers and the drill driver point to set them. They are available at both Home Depot & Lowes.

Thanks all. So is there a specific code for this? I think my town uses the national standards.

"I think my town uses the national standards."

Manufacturers instructions plus any other additional code requirements.