(b) at
work throughout the time when the officer is on duty or lawfully performing
the functions of a police officer, but not otherwise.
(3) The person
conducting the business or undertaking is also a
"worker" if the person is an individual who carries out work in that business
or undertaking.
Note : A person may be both a
"worker" , within the meaning of this section, and a
"person conducting a business or undertaking" within the meaning of section 5.