M1 M2 M3

1. For districts without an A suffix
   
   In all districts, other than districts with an A suffix, along such portion of the rear lot line of a zoning lot in a Manufacturing District which coincides with a rear lot line of a zoning lot in an adjoining Residence District, an open area not higher than curb level and at least 30 feet in depth shall be provided within the Manufacturing District. Such an open area shall not be used for storage or processing of any kind.
2. For districts with an A suffix
   
   For districts with an A suffix, where the portion of a rear lot line of a zoning lot coincides with the rear lot line of an adjoining Residence District, an open area not higher than 30 feet above curb level and at least 20 feet in depth shall be provided.