(a) Except as provided under subsection (b) of this section, the driver of a motor vehicle shall not use a handheld wireless telephone while operating a motor vehicle in a highway work zone when a highway worker is present.
(b) The driver of a motor vehicle who is in a highway work zone when a highway worker is present may use a handheld wireless telephone while operating a motor vehicle for an emergency purpose.
(c) This section does not apply to law enforcement officers.