Designing labs, research buildings: Building automation and controls
Labs and research facilities house sensitive equipment and must maintain very rigid standards. In this discussion, the engineers will discuss building automation and controls.
Nedzib Biberic, PE, LEED BD+C, Mechanical Engineer, PAE Consulting Engineers, Portland, Ore.
Michael Chow, PE, CxA, LEED AP BD+C, Member/Owner, Metro CD Engineering LLC, Powell, Ohio
David S. Crutchfield, PE, LEED AP, Division Manager, RMF Engineering, Baltimore
Dave Linamen, PE, LEED AP, CEM, Vice President, Stantec, Edmonton, Alberta
Jay Ramirez, Senior Vice President, ESD Global, Chicago
CSE: What are some common problems you encounter when working on such systems?
Ramirez: When working with science and institutional clients, particularly in manufacturing and R&D, it is important to know that these entities most often have their own internal facility management system (FMS). Most often these will be a programmable logic controller (PLC) that must interface with direct digital controls (DDC) or a building automation system (BAS). Often the FMS stores proprietary client information and is highly secured, which requires special consideration and networking to receive approval from the client. Understanding the level of communication interface and determining the proper integration methodology is absolutely critical to avoid system incompatibility and change order cost once the project is in construction.
Linamen: Lack of seamless interoperability. More components are achieving interoperability, but there are still a number that don’t, and some components have limited interoperability. Also, there are very few vendors who really have all of the components to control all HVAC systems and equipment in a lab building, so if competition is desired in the pricing of the controls, interoperability with multiple vendors is important.
Biberic: Most of the time the chosen laboratory control system is proprietary and locks the owner into one manufacturer. Also, the lack of the owner’s experience with selected lab control system is a problem; it is perceived as a “black box” and can lead to lower building efficiency or even failure of the building to perform. Most of the time, it is an independent, second control system in the building. Facilities need separate operations and maintenance (O&M) training on the system, and there is limited number of staff that interacts with the system. Integration with the BAS could be costly; mapping points from the lab control system into BAS could be time-consuming and sometimes challenging even with more experience control contractors.
CSE: What integrated systems have you specified into a recent project?
Crutchfield: The most common problem we see is that the building automation/controls systems seem to fall outside the normal preventive maintenance programs. When this happens, the tolerances that are designed into the system start to trend outside of appropriate limits slowly and over time. By the time the maintenance requests start to filter in to maintenance staff, it is often more than one control item that needs maintenance attention, so troubleshooting is necessary to track down all the problems.
Linamen: Besides sophisticated lab and fume hood controls, demand-based ventilation control that samples air quality in labs and adjusts the ventilation rate accordingly. This was for a biomedical research facility with numerous compartmentalized labs, and the demand-based control minimizes the ventilation rates in each lab by sampling the air individually in each lab and throttling the ventilation rate to maintain desired air quality. The demand-based ventilation controls can be integrated with almost any laboratory control system.
Biberic: We used Siemens and Phoenix Control on the Whitworth Science Building, a 70,000-sq-ft, three-story teaching/research laboratory facility, which consisted mostly of airflow dominated chemical laboratory spaces. The building also has a 2,000-sq-ft vivarium area, anatomy lab, and cadaver room. Laboratory spaces are served by a 100% outside air system with overhead air distribution. We installed Phoenix Controls venturi airflow valves control airflow in each lab space. In-duct mounted hydronic heating coils maintain the room temperature setpoints. We used American Auto-Matrix products in the Western Oregon University Science Building, a 20,000-sq-ft, two-story teaching laboratory facility consisting of chemical laboratory spaces. Laboratory spaces are served by a 100% outside air system with overhead air distribution. American Auto-Matrix airflow vales control exhaust airflow from laboratory equipment and fast acting actuators are used on supply VAV boxes and dampers controlling general lab exhaust.