How vigorous is the job profile can be noted from this very fact that the Railway recruits persons as 'Assistant Loco Pilot’. They work on freight trains for as long as 10–12 years. During this tenure they are supposed to work with experienced Train Drivers and perform only assisting work during the run of a locomotive i.e. a train. An Assistant Driver thus learns the tactics and dos and don'ts required for train operation. Thereafter they are promoted as 'Loco Pilot Saunter', after proper courses and practical trainings, wherein they are supposed to drive locomotives in sheds/yards at not more than 15 km/h speeds. After experiencing for not less than two years, they are promoted as 'Loco Pilot/Goods', who are always monitored by their respective 'Loco Inspectors'. A train has typical an Assistant Loco Pilot and a Loco Pilot on the Locomotive. The Assistants are normally common but Loco Pilots fall in various categories like Goods Drivers (or Loco Pilots used for running goods trains), Passenger Driver (Driver used to run slow moving Passenger carrying Trains), Mail Express Driver (Driver used to run high speed Passenger carrying Trains) and Rajdhani Drivers (Used for very high speed passenger carrying trains). There is yet another category of crew called 'Shunters' who operate only in yards, for moving trains within a particular station yard. Normally Shunters work alone without an Assistant.