Barrie By-law 2006-140, s. 6(3) — Noise By-law

Specifications

A sound level meter which meets the following specifications is a Type B Integrating Sound Level Meter:

• (a) the instrument will generally be a combination of microphone, amplifier, A-weighting network, computation circuit to obtain the integral of the mean square A-weighted pressure, display and a means of inhibiting the integration, but may vary from the above provided that it performs the same functions within the tolerances set out below;
• (b) the instrument may include computational circuitry to calculate and display the equivalent sound level directly;
• (c) the microphone of the instrument shall meet the specifications of clause 5 of IEC 123, except that, in addition to meeting the specifications of subclause 5.2 thereof, the microphone shall also meet the specifications of subclause 5.2 amended by the substitution therein of an angle of incidence of ± 30 instead of ± 90, as it therein appears, and by the substitution of Table 102-2 hereof instead of Table 1, as it therein appears;
• (d) a windscreen shall be installed on the microphone during operation and shall not affect by more than 1 dB the tolerance prescribed in clause (c);
• (e) the sound level meter, including a microphone equipped with a windscreen, shall, when operated in the presence of wind, in- dicate a wind-induced sound level not in excess of the relevant value listed in Table 102-3;
• (f) the A-weighting network shall meet the specifications of Table II and Figure 1 of IEC 123;
• (g) the amplifier shall meet the specifications of subclauses 7.2, 7.3 and 7.11 of IEC 123; By-law 2006-140 21 Office Consolidation The Corporation of the City of Barrie Noise By-law
• (h) for each sensitivity setting of the instrument the amplifier shall have a power handling capacity at least 10 dB greater than the maximum sound level specified for that sensitivity setting;
• (i) if the computation circuit is of the sampling (digital) type,

when operating in conjunction with the microphone, windscreen,

A-weighting network and amplifier. It shall generate a signal proportional to the mean square A-weighted pressure with a 1 ±0.25 s exponential averaging time constant;

• (j) the computation circuit shall Integrate the mean square

A-weighted pressure and shall be capable of doing so on each sensitivity setting for a minimum of 6 minutes at the maximum sound level specified for that sensitivity setting;

• (k) if the computation circuit is not capable of meeting the specification of clause
• (j) with the reference therein to “6 minutes” changed to “60 minutes”, then the device shall be provided with a means to indicate to the operator when the integration capability has been exceeded;