Regulation 613-7(3) of the Highway Traffic Act exempts taxicab drivers from Section 106(3) of the Act. This section allows a person driving a motor vehicle to not wear his or her seat belt if it is while transporting a passenger for hire.
Regulation 613-7(2) of the Highway Traffic Act exempts a person transporting a passenger for hire from not being able to remove or modify the shoulder strap of the seat belt assembly, at any time. For this reason it has been argued vehicle for hire drivers cannot be charged with 'failure to wear a complete seat belt assembly' as per Section 106(3).
It should be noted that seatbelts have been proven to significantly reduce the risk of injury and death and that for this reason it is highly recommended that you wear it at all times.