Barrie By-law 2006-140, s. 3(4) — Noise By-law

Use of Instrumentation

• (a) Battery Check If the sound level meter is battery powered the condition of the battery shall be checked after the meter has been allowed to warm up and stabilize. The battery condition shall be rechecked at least once per hour during a series of measurements and at the conclusion of such measurements. The meter shall not be used unless the battery condition is confirmed to be within the range recommended by the manufacturer for proper operation.
• (b) Calibration The sound level meter shall be calibrated after the meter has been allowed to warm up and stabilize, at least once per hour during a series of measurements and at the conclusion of such measurements.
• (c) Sound Level Meter Settings Measurements shall be taken using the following response settings:
• (i) Impulse Response (dBAI) The impulse response and A-weighting shall be used for impulsive sound in category
• (i) of clause 3 (1)(a). An ‘impulse hold’ facility may be used if available on the meter.
• (ii) Slow Response
• (dBA) The slow response and A-weighting shall be used for sound in categories (ii),
• (iii) or
• (iv) of clause 3 (l)(a).
• (d) Instrument Configuration
• (i) Reflective Surfaces The microphone shall be located not less than 1 m above the ground, not less than 1 m from any sound reflective surface

except for the purposes of clause 3(3)(b) and not less than arm’s length from the body, of the person operating the meter. Not more than one person, other than the operator of the meter, shall be within 7 m of the microphone and that person shall be behind the operator of the meter. For the case of clause 3(3)(b) the microphone shall be in the middle of the aperture located not less than 15 cm from the window frame or door frame. By-law 2006-140 28 Office Consolidation The Corporation of the City of Barrie Noise By-law

• (ii) Microphone Orientation The microphone shall be oriented such that the sound to be measured is incident at an angle recommended by the microphone manufacturer for flattest frequency response in a free field.
• (e) Measurement - Slow Response
• (i) Readings Taken For sound in categories (ii),
• (iii) or
• (iv) of clause 3 (1)(a), a minimum of three observations with a minimum observation time of 15 s each shall be made. The observed average reading for each of the observations shall be noted as well as the minimum and the maximum of the range of sound levels during each observation period. If the difference between any two observed average readings is greater than 3 dB, a minimum of six observations shall be made. For the purpose of adjustments for intermittency the duration of the sound in any one hour shall be noted.
• (ii) Readings Reported The arithmetic mean of the observed average readings shall be reported, rounded to the nearest decibel. Adjustments for intermittence and quality of sound shall be made in accordance with Publication NPC-104 - Sound Level Adjustments, and the result shall be reported. The result is the one hour equivalent sound level
• (Leq) of the sound under study for any one hour period during which the readings were taken pursuant to subclause (i).
• (iii) Wide Variation of Sound Levels If, in making observations pursuant to subclause (i), there is a difference of more than 6 dB between the lowest and highest values of the observed ranges of sound levels, this procedure shall not be used unless the lower limit of each such range is above the maximum permissible level. Instead, the procedure set out in Section 4 - Procedure for Measurement of Varying Sound at a point of reception, shall be used.
• (f) Measurement – Impulse Response - Frequent Impulses
• (i) Readings Taken For sound in category
• (i) of clause 3 (i)(a) not less than 20 impulses shall be measured within a continuous period of 20 minutes and each measurement taken shall be reported.
• (ii) Extension of Time

Where a minimum of 20 impulses cannot be measured within a continuous period of 20 minutes pursuant to subclause

• (i) the time period may be extended to 2 hours if an impulse occurred in each of the four consecutive periods of five minutes each during the Initial 20 minute measurement period.
• (iii) Level Reported The Logarithmic Mean Impulse Sound Level
• (LLM) of the 20 or more measurements shall be calculated and reported to the nearest decibel. This Logarithmic Mean Impulse Sound Level is

a valid and effective sound level or any one hour period during which readings were taken pursuant to subclauses

• (i) and (ii).
• (g) Measurement - Impulse Response - Single Event Readings Taken and Reported For impulsive sounds in category
• (i) of clause 3(1)(a), that occur as single, seemingly independent events not normally measurable using the procedure set out in clause
• (f) for frequent impulses, each impulse shall be independently measured and each impulse sound level reported to the nearest decibel. By-law 2006-140 29 Office Consolidation The Corporation of the City of Barrie Noise By-law
• (h) Variation in Calibration Measurements shall not be reported if the sound level meter calibration has changed more than 0.5 dB from the previous calibration.
• (i) Weather Conditions
• (i) Wind Measurements shall not be taken unless the wind-induced sound level is more than 10 dB below the measured levels. Reference should be made to Publication NPC-102 - Instrumentation, particularly Table 102-3.
• (ii) Humidity Measurements shall not be taken if the relative humidity is above the maximum for which the meter specification is guaranteed by the manufacturer (normally 90%).
• (iii) Precipitation Measurements shall not be taken during precipitation.
• (iv) Temperature Measurements shall not be taken when the air temperature is outside the range for which the specification of the instrument is guaranteed by the manufacturer. (Normally, only the lower temperature limit is significant.)