On Board Trains Occupational Health and Safety Regulations

4.3 Where the level of impulse sound in a work place exceeds 140 dB, the employer shall provide every employee entering the work place with a hearing protector that

• (a) meets the standards set out in CSA Standard Z94.2-M1984, Hearing Protectors, the English version of which is dated June, 1984 and the French version of which is dated February, 1985; and

• (b) reduces the peak level of impulse sound reaching the employee’s ears to 140 dB or less.