What is the difference between a building inspector and a plan inspector?

A building inspector takes a look at the physical building to ensure everything is working as it should. Defects in a building can happen over time or due to faulty construction. Inspections have to occur periodically to prevent these defects. A plan inspector, meanwhile, focuses on the blueprints during the building process. The plan inspector has to look at the plans and verify that the design itself is up to code. For example, a plan inspector must make sure the future building has emergency doors that open outward and the correct number of exits.