Steamfitters are craftsmen who assemble, install, and maintain pipes to carry water, steam, compressed air, cases, and fluids needed for processing manufacturing, heating, or cooling. The journeyman steamfitter must be able to adapt and repair pipe systems install appliances, heating and refrigeration units, and do all types of pipe welding. Steamfitters work with both high and low-pressure pipes, mainly in industrial and commercial buildings. They also install and repair residential heating and cooling equipment. Certified welding is often required for a particular job and is part of the educational process. There are limited apprenticeships in Marine Pipefitting.