331.45 NOISE LEVELS FOR MOTOR VEHICLES.
(a) The following definitions are applicable to this section only:
(1) "Ambient noise" means the all-encompassing noise associated with a given environment, being usually a composite of sounds from many sources, near and far.
(2) "ANSI" means the American National Standards Institute or its successor bodies.
(3) “Frequency" means the complete sequence of values of a periodic quantity that occurs during a period and is referred to as cycles per second or Hertz.
(4) "db(a)" means the "A" weighted scale for measuring sound levels as defined in ANSI S1. 4-1971, or the latest approved revision thereof.
(5) "Decibel" means a unit of level which denotes the ratio between two quantities that are proportional to power; the number of decibels corresponding to the ratio of two amounts of power is ten times the logarithm to the base ten of this ratio.
(6) "Motor vehicle" includes, but is not limited to automobiles, trucks, motorcycles, minibikes and go-carts. "Person" means any person, firm, association, copartnership, joint venture, corporation or any entity public or private in nature. "Sound analyzer" means a device for measuring a specific band pressure level or pressure spectrum level of a sound as a function of frequency. "Sound level meter" means an instrument including a microphone, an amplifier, an output meter, and frequency weighing networks for the measurement of noise and sound levels in a specified manner. The meter must satisfy the applicable requirements for Type 1 or 2 (general purpose) sound level meters as defined in ANSI S1.4-1971 or the most recent revision and the meter must be set for slow response speed, except that for rapidly varying sound levels, fast response speed may be used.
(b) No person shall operate a motor vehicle which creates a noise or sound which exceeds the noise limits set forth in this subsection:
(1) Passenger cars. Ninety db(A) when measured twenty inches from the rear of the exhaust pipe at a forty-five degree angle to the center of the pipe at a minimum height of eight inches from a hard surface.
(2) Motorcycles. Ninety-five db(A) when measured twenty inches from the rear of the exhaust pipe at a forty-five degree angle to the center of the pipe at a minimum height of eight inches from a hard surface.
(3) Trucks. Trucks over 6,000 pounds G.V.W., with vertical exhaust, when measured at eighteen inches from the side of the exhaust, and four feet above the ground parallel with the exhaust system shall not exceed ninety-eight db(A).
(4) Trucks with horizontal exhaust and buses. Ninety-eight db(A) when measured twenty inches from the rear of the exhaust pipe at a forty-five degree angle to the center of the pipe at a minimum height of eight inches from a hard surface.
(c) Exemptions. Fire Division vehicles are exempt from the provisions of this section.
(d) Testing procedures shall be those prescribed by the Chief of Police from standard or widely recognized methods including but not limited to; American National Standards Institute or Society of Automotive Engineers.
(Ord. 76-68. Passed 2-17-76.)
(e) Whoever violates any provision of this section is guilty of a minor misdemeanor on a first offense; on a second offense within one year after the first offense, the person is guilty of a misdemeanor of the fourth degree; on each subsequent offense within one year after the first offense, the person is guilty of a misdemeanor of the third degree.