M1 M2 M3

In all districts, as indicated, along such portion of the boundary of a Manufacturing District which coincides with a side lot line of a zoning lot in an R1, R2, R3, R4 or R5 District, an open area not higher than curb level and at least 15 feet wide shall be provided within the Manufacturing District. Such an open area shall not be used for accessory off-street parking, accessory off-street loading, or for storage or processing of any kind.