Building Automation Systems (BAS) Technicians apply knowledge of various building trades such as electrical, mechanical, telecommunications, and information systems networks to computer-based control systems and building automation and environmental control energy equipment in commercial and industrial buildings. They interface with customers, architects, engineers, and contractors to install and service building automation systems including project start‐up and commissioning in office buildings, industrial properties, medical centers, hotels, malls, retail stores, and warehouses. BAS Technicians are responsible for troubleshooting, fixing, and updating HVAC systems and associated controls; downloading, updating and verifying software accuracy; and calibrating and testing HVAC systems and controls. BAS Technicians must be well versed in a variety of building systems including: environmental energy equipment such as heating, ventilation, and air-conditioning systems, heat pumps, and boilers; air handlers, variable air volume and mixing boxes; chillers and related equipment; lighting controls; security and access controls; irrigation and fire alarm interfaces; and water leak detection.

Building automation is the automatic centralized control of a building's heating, ventilation and air conditioning, lighting and other systems through a building management system or building automation system. Building automation is an important advancement in energy efficiency design and can lower a building's overall energy consumption.