Diesel locomotive
Diesel locomotives offer significant operating advantages over steam locomotives. They can safely be operated by one person, making them ideal for switching/shunting duties in yards (although for safety reasons many main-line diesel locomotives continue to have 2-man crews: an engineer and a conductor/switchman) and the operating environment is much more attractive, being quieter, fully weatherproof and without the dirt and heat that is an inevitable part of operating a steam locomotive. Diesel locomotives can be worked in multiple with a single crew controlling multiple locomotives in a single train — something not practical with steam locomotives. This brought greater efficiencies to the operator, as individual locomotives could be relatively low-powered for use as a single unit on light duties but marshaled together to provide the power needed on a heavy train. With steam traction a single very powerful and expensive locomotive was required for the heaviest trains or the operator resorted to double heading with multiple locomotives and crews, a method which was also expensive and brought with it its own operating difficulties.
Motive power depot
The maintenance of the new diesel locomotives in filthy steam sheds soon proved difficult and although some old sheds survived, many new diesel depots were built on new sites or on the sites of the old steam sheds. The major problem was the disposal of oil which initially was left lying around causing pollution and safety issues. The new depots were equipped to deal with diesel fuel and the ability to access the underside as well as upper body work was improved.
The tasks were not that much different in that diesel locomotives were fuelled rather than coaled (although they did require water as early diesels were equipped with steam generators for train heating purposes).