2.1 The following definitions apply in this Part.

“A-weighted sound pressure level”

“A-weighted sound pressure level” means a sound pressure level as determined by a measurement system that includes an A-weighting filter that its manufacturer represents as meeting the requirements set out in the International Electrotechnical Commission International Standard IEC 61672-1:2002(E), 1st edition 2002-2005 Electroacoustics – Sound Level Meters. (niveau de pression acoustique pondérée A)

“dBA”

“dBA” means decibel A-weighted and is a unit of A-weighted sound pressure level. (dBA)

“noise exposure level (L_ex,8)”

“noise exposure level (L_ex,8)” means 10 times the logarithm to the base 10 of the time integral over any 24-hour period of a squared A-weighted sound pressure divided by 8, the reference sound pressure being 20 μPa. (niveau d’exposition (L_ex,8))

“sound level meter”

“sound level meter” means a device for measuring sound pressure level that its manufacturer represents as meeting the performance requirements for a Type 2 instrument as specified in the International Electrotechnical Commission International Standard IEC 61672-1:2002(E), 1st edition 2002-2005 Electroacoustics – Sound Level Meters. (sonomètre)

“sound pressure level”

“sound pressure level” means 20 times the logarithm to the base 10 of the ratio of the root mean square pressure of a sound to the reference sound pressure of 20 μPa, expressed in decibels. (niveau de pression acoustique)

• 2.2 (1) For the purposes of this Part, the exposure of an employee to sound shall be measured using an instrument that

  • (a) is recommended for that measurement in clause 4.3 of CSA Standard CAN/CSA-Z107.56-06, Procedures for the Measurement of Occupational Noise Exposure; and

  • (b) is certified, by a certification body accredited by the Standards Council of Canada to grant the certification, as meeting the requirements for such an instrument set out in clause 4 of that Standard.

• (2) The exposure of an employee to sound shall be measured in accordance with clauses 5, 6.4.1, 6.4.4, 6.5.2, 6.5.4, 6.6.2 and 6.6.4 of the Standard referred to in paragraph (1)(a).

• (3) For the purposes of this Part, the measurement and calculation of the noise exposure level (L_ex,8) to which an employee is exposed shall take into account their exposure to A-weighted sound pressure levels of 74 dBA and greater.

• (4) For the purposes of this Part, the measurement and calculation of the noise exposure level (L_ex,8) may also take into account the exposure of the employee to A-weighted sound pressure levels that are less than 74 dBA.