Plumbers are responsible for maintaining water fixtures and systems for residential and commercial buildings. They can also work with gas systems in homes ensuring they are properly installed. They install plumbing fixtures including showers, sinks, toilets, and bathtubs. They can also work with some outdoor water facilities. They may also install appliances including dishwashers, waste disposals, and water heaters. They maintain the pipes etc. that run water in and out of residential and commercial buildings.