23(1)An employer shall ensure that a system is installed and maintained for communicating by voice between persons at an attended place on the surface and
(a)
the collar of the shaft including the collar of an internal shaft,
(b)
each landing station in use in a shaft,
(c)
the hoist room for the shaft including the hoist room for an internal shaft,
(d)
each underground refuge station, and
(e)
each continuous mining machine.
23(2)If the system referred to in subsection (1) uses radio frequencies, an employer shall obtain and keep a certificate from an engineer stating that the system is suitable for underground use.
23(3)If the level of ambient noise in an area renders the audible warning signal of the system referred to in subsection (1) inaudible, the system shall be equipped with a visual warning signal.
23(1)An employer shall ensure that a system is installed and maintained for communicating by voice between persons at an attended place on the surface and
(a)
the collar of the shaft including the collar of an internal shaft,
(b)
each landing station in use in a shaft,
(c)
the hoist room for the shaft including the hoist room for an internal shaft,
(d)
each underground refuge station, and
(e)
each continuous mining machine.
23(2)If the system referred to in subsection (1) uses radio frequencies, an employer shall obtain and keep a certificate from an engineer stating that the system is suitable for underground use.