Operating performance standards

• (1) Noise shall be measured with a sound level meter meeting the standards of the American National Standards Institute (ANSI S1. 1961) American Standard Specification for General-Purpose Sound Level Meters. The instrument shall be set to the A-weighted response scale and the meter to the slow response. Measurements shall be conducted in accordance with ANSI S1.2 (1962), American Standard Method for the Physical Measurements of Sounds.
• (2) Table I specifies the noise limits that apply on or beyond adjacent lot lines or zone boundaries outside the user's property. Noises shall not exceed the maximum sound levels specified in Table I, except as designated following Table I. Where more than one specified sound level applies, the most restrictive shall govern. Measurements may be made at points of maximum noise intensity.

  	Table I Noise Level Restrictions
  	Maximum Permitted Sound Level* (dBA)	Measured Across and Outside
  	55	Rural, Farming, Residential District lot lines
  	60	Industrial A District boundary lines
  	65	Industrial B District boundary lines

  *

  In any Rural, Farming and Residential Zones, the weighted sound level shall not exceed 55 dBA between 7:00 a.m. and 7:00 p.m. and shall not exceed 45 dBA between 7:00 p.m. and 7:00 a.m.

• (3) The levels specified in Table I may be exceeded by 10 dBA for a single period, no longer than 15 minutes, in any one day.
• (4) For impact noise levels, the values in Table I, increased by 20 dBA, shall apply. Impact noises shall be considered to be those noises whose peak values are more than six dBA higher than the values indicated on the sound level meter.
• (5) Exemptions. The following uses and activities shall be exempt from the noise level regulations:
  • (a) Noises not directly under the control of the property user.
  • (b) Noises emanating from construction and maintenance activities between 7:00 a.m. and 7:00 p.m., Monday through Saturday.
  • (c) The noises of safety signals, warning devices, and emergency pressure-relief valves.
  • (d) Transient noises of moving sources such as automobiles, trucks, airplanes and railroads.

Editor's Note: See also Ch. 269, Noise.

• (1) Ground-transmitted vibration shall be measured with an accelerometer or complement of instruments capable of recording vibration displacement and frequency, particle velocity, or acceleration simultaneously in three mutually perpendicular directions.
• (2) Maximum permitted vibration levels.
  • (a) No vibration at any time shall produce a maximum peak particle velocity which exceeds the following values measured on or beyond the appropriate lot or district boundaries given below:

    	Table II Maximum Peak Particle Velocity (inches/second)
    			Measured On or Beyond
    	Character of Vibrations	Adjacent Lot Line	Neighborhood or Highway Business District Boundary	Rural, Farming, Residential District Boundary
    	Steady-state	0.10	0.05	0.02
    	Impact	0.20	0.10	0.04

    *

    Steady-state vibrations shall be considered as vibrations which are continuous, or vibrations in discrete impulses more frequent than 60 per minute. Discrete impulses which do not exceed 60 per minute shall be considered impact vibrations.

  • (b) Between 7:00 p.m. and 7:00 a.m., all of the permissible vibration levels indicated in the previous table for Rural, Farming, and Residential District boundaries shall be reduced to 1/2 of the indicated values.

• (1) Illumination levels shall be measured with a photoelectric photometer having a spectral response similar to that of the human eye, following the standard spectral luminous efficiency curve adopted by the International Commission on Illumination.
• (2) Uses subject to performance standards shall not produce glare so as to cause illumination in Rural, Farming, and Residential Districts in excess of 0.05 footcandle. Flickering or intrinsically bright sources of illumination shall be controlled so as not to be a nuisance in residential districts. Exterior lights shall reflect light away from adjoining property in any Rural, Farming and Residential District.
• (3) Uses subject to performance standards shall limit the use of light sources and illuminated surfaces within 500 feet of, and visible in, a Rural, Farming and Residential District to comply with the light intensities indicated below.

  	Table III Maximum Intensity of Light Sources
  	Source	Intensity
  	Bare incandescent bulbs	40 watts
  	Illuminated buildings	30 footcandles
  	Back-lighted or luminous background signs	250 footlamberts
  	Outdoor illuminated signs and poster panels	50 footcandles
  	Any other unshielded sources, intrinsic brightness	50 candles per square centimeter

• (1) Sewage and water-borne wastes shall be disposed of in a manner acceptable to the Director of the Rhode Island Department of Environmental Management, and the design, installation and operation of all subsurface wastewater disposal systems shall be approved by the Director of the Rhode Island Department of Environmental Management.
• (2) Effluent discharges into a surface water body shall require issuance of a National Pollutant Discharge Elimination System (NPDES) permit by the United States Environmental Protection Agency and the Rhode Island Department of Environmental Management.

Editor's Note: See also Ch. 301, Sewage and Garbage Disposal.