17-602. State outdoor shooting range noise standards; preemption; measurement; definitions

A. The legislature finds that outdoor shooting range noise standards are a matter of statewide concern. City, town, county and any other state noise standards are preempted as applied to outdoor shooting ranges.

B. Each outdoor shooting range in this state shall measure the noise emitted from the range pursuant to subsection E at least once. In addition, the range shall measure the noise it emits if the range expands the area designed and operated for the use of firearms or explosives by more than twenty per cent in size than at the time of its initial noise measurement or if the range introduces the use of a type of firearm or explosive device that will increase noise production. The range shall pay for the measurement and shall keep the results of the measurement at the range at all times. Any person may review the noise measurement during the range's business hours. Ranges that are located at least one mile from areas that are zoned for residences, schools, hotels, motels, hospitals or churches are exempt from this subsection.

C. Any person, at the person's expense, may measure the noise emitted from an outdoor shooting range pursuant to subsection E.

D. The noise emitted from an outdoor shooting range shall not exceed an Leq(h) of sixty-four DBA.

E. In measuring the noise emitted from an outdoor shooting range:

1. If a range performs the measurement of noise pursuant to subsection B, sound pressure measurements shall be taken twenty feet from the nearest occupied residence, school, hotel, motel, hospital or church, or from the nearest proposed location of a residence, school, hotel, motel, hospital or church if the property is zoned for such a structure but is currently unimproved. If a person performs the measurement of noise pursuant to subsection C, sound pressure measurements shall be taken twenty feet from the person's residence, school, hotel, motel, hospital or church, or twenty feet from the proposed location of the person's residence, school, hotel, motel, hospital or church if the property is zoned for such a structure but is currently unimproved.

2. Sound pressure measurements shall be made in a location directly between the range and the nearest existing or proposed residence, school, hotel, motel, hospital or church. If there are natural or artificial obstructions that prevent an accurate noise measurement, the measurement may be taken within an additional twenty feet radius from the initial measurement location.

3. Sound pressure measurements shall be made on the A-weighted fast response mode scale. Measurements shall be taken during the noisiest hour of peak use during the operation of the range. Measurements shall be taken according to American national standards institute's standard methods ANSI S1.2-1962 (R1976) American national standard method for physical measurement of sound and ANSI S1.2-1971 (R1976) American national standard method for measuring sound pressure levels. Measurements shall be taken using a type 1 sound meter meeting the requirements of ANSI S1.4L-1971. Any part of the measurements conducted on a range shall comply with the range safety rules.

F. Outdoor shooting ranges in operation on July 1, 2002 shall comply with the provisions of this section before July 1, 2003. Ranges not in operation on July 1, 2002 shall comply with the provisions of this section when they begin operation.

G. Subsection B does not apply to an outdoor shooting range that is built for military or armed nuclear security guard training and that is not open to the general public.

H. For the purposes of this section:

1. " A-weighted" means a frequency weighting network used to account for changes in sensitivity as a function of frequency.

2. " DBA" means A-weighted decibels, taking into account human response to sound energy in different frequency bands.

3. " Decibel" means the unit of measure for sound pressure denoting the ratio between two quantities that are proportional to power. The number of decibels is ten times the base ten logarithm of this ratio.

4. " Leq(h)" means the equivalent energy level that is the steady state level that contains the same amount of sound energy as a time varying sound level for a sixty minute time period.