Because deliverables are often the contractual or formal work products of an architectural project, they are likely to be limited or amended by any enterprise-wide project or process management (such as CMMI, PRINCE2, PMBOK, or MSP). The most common types of architectural deliverables include: Design documents: These include detailed drawings and other documentation required to construct a building or other physical facility. Design documents may include specifications for materials, labor, and equipment; site plans; elevations; sections; details; and diagrams. Schematics: These provide a visual representation of an electrical system, plumbing network, or other internal structure or arrangement of elements. Schematics are used by engineers and architects to identify connections and components quickly during design reviews or when preparing paperwork such as permits or contracts. Permits: These are the governmental documents that authorize construction activities on specific projects. In the United States, federal agencies such as the Federal Highway Administration (FHWA) and National Park Service (NPS), state agencies like the California Department of Transportation (Caltrans), and local governments like city planning departments, issue construction permits. Agencies may have requirements for certain types of designs that must be approved by staff architects before a permit can be issued. Compliances: These are documents or reports from various organizations or individuals which confirm that a product or service meets applicable laws and regulations.