(b)
Except as provided in subsection (f) of this section, the table set forth in subsection (e) of this section establishes the maximum permissible noise levels for 4.000 classification uses in the Light Industrial and General Industrial districts. Measurements shall be taken at the boundary line of the lot where the 4.000 classification use is located, and, as indicated, the maximum permissible noise levels vary according to the zoning of the lot adjacent to the lot on which the 4.000 classification use is located.
(c)
A decibel is a measure of a unit of sound pressure. Since sound waves having the same decibel level "sound" louder or softer to the human ear depending upon the frequency of the sound wave in cycles per second (i.e., whether the pitch of the sound is high or low) an A-weighted filter constructed in accordance with the specifications of the American National Standards Institute, which automatically takes account of the varying effect on the human ear of different pitches, shall be used on any sound level meter taking measurements required by this section. And accordingly, all measurements are expressed in dB(A) to reflect the use of this A-weighted filter.
(d)
The standards established in the table set forth in subsection (e) of this section are expressed in terms of the equivalent sound level (Leq), which must be calculated by taking 100 instantaneous A-weighted sound levels at 10-second intervals (see the administrative guideline entitled "Guide for Noise Levels," Section F-1) and computing the Leq in accordance with the table set forth in the administrative guideline entitled "Guide for Noise Levels," Section F-2.
(e)
Table 14.44-I: Maximum Permitted Sound Levels, dB(A).
Table 14.44-I: Maximum Permitted Sound Levels, dB(A) | |||||
|---|---|---|---|---|---|
Zoning of Lot Where 4.000 Use Located | (re: 0.0002 Microbar) Zoning of Adjacent Land | ||||
Residential and PND | NC, LB, CBD, MU, PBD | LI | GI | ||
7:00 a.m. - 9:00 p.m. | 9:00 p.m. - 7:00 a.m. | ||||
LI & GI | 60 | 50 | 65 | 70 | 70 |
(f)
Impact noises generated by sources that do not operate more than one minute in any one-hour period are permissible up to a level of 10 dB(A) in excess of the figures listed in subsection (e) of this section, except that this higher level of permissible noise shall not apply from 9:00 p.m. to 7:00 a.m. when the adjacent lot is zoned residential. The impact noise shall be measured using the fast response of the sound level meter.
(g)
Noise resulting from temporary construction activity that occurs between 7:00 a.m. and 9:00 p.m. shall be exempt from the requirements of this section.
(Ord. 468, 1995; Ord. 590, 1998; Ord. 811, Sec. 46, 2010; Ord. 1124, Sec. 2 (Exh. A), 2021; Ord. 1179, Sec. 12, 2024)
(a)
No subject use in any permissible business district may generate any ground-transmitted vibration that is perceptible to the human sense of touch measured at (1) the outside boundary of the immediate space occupied by the enterprise generating the vibration if the enterprise is one of several located on a lot, or (2) the lot line if the enterprise generating the vibration is the only enterprise located on a lot.
(b)
No subject use in a Light Industrial or General Industrial district may generate any ground-transmitted vibration in excess of the limits set forth in subsection (e) of this section. Vibration shall be measured at any adjacent lot line or residential district line as indicated in the table set forth in subsection (d) of this section.
(c)
Vibrations resulting from temporary construction activity that occurs between 7:00 a.m. and 9:00 p.m. shall be exempt from the requirements of this section.
(d)
The vibration maximums set forth in subsection (e) of this section are stated in terms of particle velocity, which may be measured directly with suitable instrumentation or computed on the basis of displacement and frequency.
When computed, the following formula shall be used:
PV = 6.28 F x D
Where:
PV = Particle velocity, inches-per-second
F = Vibration frequency, cycles-per-second
D = Single amplitude displacement of the vibration, inches.
The maximum velocity shall be the vector sum of the three components recorded.
(e)
Table 14.44-II: Table of Maximum Ground-Transmitted Vibration.
Table 14.44-II: Maximum Ground-Transmitted Vibration | ||
|---|---|---|
Zoning District | Particle Velocity, Inches-Per-Second | |
Adjacent Lot Line | Residential District | |
M-1 | 0.10 | 0.02 |
M-2 | 0.20 | 0.02 |
(f)
The values stated in subsection (e) of this section may be multiplied by two for impact vibrations, i.e., discrete vibration pulsations not exceeding one second in duration and having a pause of at least one second between pulses.
(g)
Vibrations resulting from temporary construction activity that occurs between 7:00 a.m. and 9:00 p.m. shall be exempt from the requirements of this section.
(Ord. 811, Sec. 92, 2010; Ord. 1124, Sec. 2 (Exh. A), 2021)
(a)
For purposes of this section, the "odor threshold" is defined as the minimum concentration in air of a gas, vapor, or particulate matter that can be detected by the olfactory systems beyond the subject property.
(Ord. 1124, Sec. 2 (Exh. A), 2021)
(a)
Any subject use that emits any "air contaminant" as defined in Regulations I, II, or III of the Puget Sound Clean Air Agency shall comply with applicable state standards concerning air pollution.
(b)
No Planning Director approval, administrative conditional use, or conditional use permit may be issued with respect to any development covered by subsection (a) of this section until the Puget Sound Clean Air Agency has certified to the permit-issuing authority that the appropriate State permits have been received by the developer, or that the developer will be eligible to receive such permits and that the development is otherwise in compliance with applicable air pollution laws.
(Ord. 811, Sec. 47, 2010; Ord. 903, Sec. 35, 2013; Ord. 1124, Sec. 2 (Exh. A), 2021)
No subject use shall consume and/or use water supplied by the Snohomish County Public Utility District No. 1 in a manner inconsistent with the requirements and water service policies of the Snohomish County Public Utility District No. 1.
(Ord. 1124, Sec. 2 (Exh. A), 2021)
No subject use may:
(a)
Create any electrical disturbance that adversely affects any operations or equipment other than those of the creator of such disturbance; or
(b)
Otherwise cause, create, or contribute to the interference with electronic signals (including television and radio broadcasting transmissions) to the extent that the operation of any equipment not owned by the creator of such disturbance is adversely affected.
(Ord. 1124, Sec. 2 (Exh. A), 2021)