1. The Ringlemann Chart, as adopted and published by the United States Department of Interior, Bureau of Mines, shall be used to determine the density of equivalent opacity of smoke. The Ringlemann number indicated as the performance standard in certain zoning districts refers to the number of the area of the Ringlemann Chart that coincides most nearly with the visual density of equivalent opacity of the emission of smoke observed.

2. Within the M-1, M-2 and M-3 zoning districts, no use shall be permitted or operated so that smoke darker than Ringlemann No. 1 is produced from any vent, stack or chimney. However, emission of smoke darker than Ringlemann No. 2 is allowed for a duration of up to four (4) minutes during any eight (8) hour period if the emission is located no closer than two hundred fifty (250) feet from property zoned AG, any residential zoning district, N, or the residential areas of planned developments.

3. Particulate matter emissions in excess of the threshold limit values caused by the wind from open storage areas, yards, roads, etc., within lot lines shall be kept to a minimum by appropriate landscaping, paving, oiling, wetting and other means, or shall be eliminated.

1. No use within a quarry or use within properties zoned M-1, M-2 and M-3 may generate any ground-transmitted vibration for three (3) consecutive minutes or more in duration in any one (1) hour in excess of one-tenth (0.10) inch per second measured at the property line, or in excess of two-one hundredths (0.02) inch per second measured at any residential property line. These values may be multiplied by two (2) for impact vibrations, i.e., discrete vibration pulsations not exceeding one (1) second in duration and having a pause of at least one (1) second between pulses. Vibrations are measured in particle velocity and are to be measured at the property line or other designated location.

2. A three-component measuring system capable of simultaneous measurement of vibration in three (3) mutually perpendicular directions shall be used to measure vibrations. Upon request of the City, the owner or operator of a use subject to this section will install said measuring system at the property line of the use or on the residential property of a complainant with the property owner’s consent.

3. The vibration maximums indicated as the performance standard in certain zoning districts must be measured directly with suitable instrumentation in accordance with the International Society of Explosive Engineers (ISEE) Field Practice Guidelines for Blasting Seismographs or other applicable guidelines for this type of measurement.

4. The provisions of this subsection shall not apply to vibration from:

1. Within the M-1, M-2 and M-3 districts, direct or sky-reflected glare, from floodlights or from high temperature processes such as combustion or welding, shall not be directed into any adjoining property.