Pumps, fans, and compressors transparently move water, air, and refrigerant through every building in North America. These systems are invisible no more. During normal operation all three mediums contribute to the mode of transmission that can impact the health of the building occupants. Practices and protocols to safely reopen buildings are offered by many organizations to promote public confidence. To safeguard the experience for building occupants, workers, and employees all building owners need to rely on qualified contractors at every level to make responsible decisions about building operations. What does that mean? Which standard or guideline is relevant to the building systems? This session will explore standard practices and new technologies presented to contractors, building owners, authorities having jurisdiction, facility managers, and service technicians.