The provisions of this article shall not apply to salvage yards or any parts thereof within municipalities situated in areas zoned industrial, nor to salvage yards or any parts thereof situated in areas within municipalities not zoned industrial but which the commissioner determines are used for industrial activities. The provisions of section four of this article shall not apply to salvage yards within municipalities in existence on the effective date of this article but not required to be licensed under the former provisions of this article, if the view of said salvage yards is effectively screened from the adjacent road by fences.