Where commercial uses are located either on the same story as dwelling units, or on a higher story, pursuant to the applicable provisions of Section 32-421 and 32-422, the provisions of this Section shall apply to uses listed in Use Group VI, as set forth in Section 32-16 (Use Group VI – Retail and Services), inclusive, uses listed in Use Group VIII, as set forth in Section 32-18 (Use Group VIII – Recreation, Entertainment and Assembly Spaces), inclusive, uses listed in Use Group IX, as set forth in Section 32-19 (Use Group IX - Storage) and uses listed in Use Group X, as set forth in Section 32-20 (Use Group X – Production Uses).

1. Air quality
   
   Where a use listed in Use Group X is required to install an emission stack by Federal, State or Local law, such stack shall exhaust above the height of building containing such use, or above the height of the immediately adjacent buildings, whichever is higher.
2. Noise
   
   Above the level of the first story, where the applicable commercial uses are located on the same story as a dwelling unit or a story higher than a dwelling unit, such uses shall either:
   1. be separated from dwelling units by a horizontal or vertical distance of at least 15 feet and includes at least two wall or ceiling partitions, as applicable; or
   2. provide attenuation that will result in a sound level below 42 dBA for daytime and 35 dBA for nighttime, as measured from the interior of the closest dwelling units. Such measurement shall be verified by an acoustical engineer prior to the issuance of a certificate of occupancy by the Department of Buildings.
3. Vibration
   
   Above the level of the first story, where the applicable commercial uses are located on the same story as a dwelling unit or a story higher than a dwelling unit, such uses shall be subject to the provisions of Section 42-22 (Performance Standards Regulating Vibration) for an M1 District, except that the measurements for maximum vibration displacements shall be measured within the building instead of at the lot line. Such measurement shall be verified by a vibration or acoustical engineer prior to the issuance of a certificate of occupancy by the Department of Buildings.