Within the Fire Department there shall be a class higher than Firefighter, known as Firefighter-Paramedic, based on the attainment of certification and/or registration by a competent State or Federal authority as an Emergency Medical Technician Paramedic, subsequent to successful completion of an appropriate course of study prerequisite to such certification and/or registration. Except as may be otherwise provided in this chapter, any employee of the Department who qualifies as such shall be entitled to his or her Firefighter salary, plus an additional one thousand five hundred dollars ($1,500) annually, to be distributed at normal payroll intervals with such salary. Such combined salary shall constitute the base salary for determining the overtime rate for the class known as Firefighter-Paramedic.