On Board Trains Occupational Health and Safety Regulations

4.1 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 which includes an A-weighting filter that meets the requirements set out in the International Electrotechnical Commission’s International Standard IEC 61672-1, first edition 2002-05, entitled 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 the level equal to 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 an instrument for measuring levels of sound and impulse sound that meets the requirements set out in the International Electrotechnical Commission’s International Standard IEC 61672-1, first edition 2002-05, entitled Electroacoustics – Sound Level Meters. (sonomètre)

sound pressure level

sound pressure level means the level equal to 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)