Yes, the transportation can record their drivers even when there is no client; employees may be recorded (other than in locker, changing, rest, etc. rooms, of course) whenever they are at work, at the employer's option. And while an employer must make "reasonable accommodations" for an employee's religion, they are allowed to prohibit prayer in their own facilities or vehicles; they can't stop their employees from praying on a lunch or other break, if they step outside the employer's facilities or vehicles, but can prohibit them praying while actually working or in the company vehicle.