July 01, 2002
Appeared in Building Operating Management/FacilitiesNet
The past decade has seen a major restructuring of the American healthcare system, with alliances among providers to heighten efficiency and create economies of scale, and smaller facilities forced to transform themselves to survive in the competitive environment. At the same time, hospitals and medical centers have watched their operating costs rise steadily. To maintain access to healthcare for as many people as possible, facilities are faced with the challenge of increasing productivity while reducing costs.
A key element in healthcare facilities today is the wide range of mechanical-electrical systems essential to their operations. In addition to the standard lighting, heating, cooling, ventilating and life safety systems, hospitals also require a variety of information systems, such as medical records databases, and specialized systems, such as air pressure and humidity control in critical areas. Therefore, energy use accounts for a significant portion of operating costs. Part of the challenge in cutting costs thus lies in improving equipment performance and reducing energy consumption without diminishing the comfort, safety or security of the healthcare environment.
Optimizing the efficiency of the mechanical-electrical systems is one approach to the problem. Accomplishing this has resulted in an ever greater degree of system automation and sparked the need for increased system integration. Now and in the future, the demand for improved performance and lower operating costs will accelerate hospitals' requirements for state of the art technology. All systems will have to be automated, and operating and control systems will also have to be able to interface with medical systems. To make this possible, healthcare facilities will increasingly need a high-speed communication infrastructure.
Westchester Medical Center Design Employs Systems Integration Approach
An example of the degree to which system integration can extend can be found in the new 290,000-sq.-ft. children's hospital and trauma center at the Westchester Medical Center in Valhalla, N.Y. Syska Hennessey Group, in association with the architects NBBJ and Lothrop Associates, is currently at work on the design of the MEP, fire protection and environmental systems for the new facility. The design team is creating a template that calls for an open protocol system using BacNet riding on a TCP/IP Ethernet backbone.
The system will integrate lighting control and electronic variable air volume boxes and provide calculations of energy use for the chiller plant to promote energy conservation. Specialized hospital systems such as those for oxygen detection in the MRI area, pressure monitoring in isolation rooms, and temperature, humidity and pressure control in operating and recovery rooms will all report back to the central building management system and interface with the fire safety system to provide for smoke exhaust. In addition, all major electrical and utility systems, as well as the backup power supply, will be monitored and metered.
Although it was possible to tie in the security network as well, the engineers chose to maintain it as a separate system. The design template allows for even greater integration in the future, as required. This facility can be viewed as a model of the current trends in design for integrating automated systems.
A mechanical-electrical design template that provides for the newest technology using open protocol communications will permit various systems to be integrated, while lowering overall operating costs. Such a design allows for interaction among the equipment of multiple manufacturers and permits the global monitoring of all critical functions at several different locations within a facility, ensuring that systems will operate as efficiently as possible and alerting operations staff to problems as soon as they occur. This enables staff to be proactive in case of malfunctions.
The first step in this process is to identify the systems that may be candidates for integration. These might include any that operate within the healthcare environment-from lighting to elevators, from ventilation, heating and cooling to electrical and emergency power systems, from laboratories to critical care systems, life safety, security and data centers.
In the past, each of these systems functioned independently, but now all can be primed for integration. However, it may not be practical to link them all. From the viewpoint of a design engineer, certain groups should remain separate since a change in one area is not likely to affect another-a drop in pressure in an isolation room, for example, doesn't impact on hospital security-but certain information can still be shared among them.
Once it has been determined which systems to integrate, a facility should decide on the strategies to employ to optimize system interoperability. This process includes defining and itemizing specific point information for key groups, to identify what information is to be shared-what is essential to each system facility operator and what is extraneous. Not everyone will need every piece of information to operate efficiently.
Monitoring of systems is another key decision; which will be monitored as part of the integration process-utilities can be metered and sub-metered, for example, to determine performance levels. In addition, how facility managers will use the integration to distribute energy costs properly should also be established. The design should allow for the partitioning of systems to attribute the correct costs to the various users and distribute the overhead over different branches of the hospital's operations. To make the integrated system function at its best, each of the components can be monitored for increased control and gauging efficiency of each equipment.
For successful implementation of system integration, a series of steps should be followed. A world-class healthcare facility requires internal and external resources, so the facility should first seek corporate support of the concept-a "champion" such as the board of trustees that will buy into the aims of sharing system technology and the methodology to achieve it and back up the program with funding.
A knowledgeable system integration engineer with an understanding of the needs and expertise in the design of healthcare facilities should be engaged to consult on and develop the design. It is also essential to determine the performance requirements-that is, what the facility wants to obtain-for each system, as well as the overall performance level desired from system integration.
Next, the optimum communication protocol must be identified. Two chief standards established and in wide proliferation within the building automation industry are BacNet and LonWorks. BacNet-Building Automation Control Network- one of the earliest attempts to allow systems to communicate on a single network, was developed to meet open protocol standards set by the American Society of Heating, Refrigeration and Air Conditioning Engineers (ASHRAE) and is currently used by many equipment manufacturers. LonWorks, developed independently by the Echelon Corporation, is a protocol based on a neuron chip.
Each piece of equipment installed in a facility contains a chip that carries its characteristics and is able to communicate with the corresponding software in the automation system. Both these protocols can be used in conjunction with the communication protocol TCP/IP.
TCP/IP-Transmission Control Protocol/Internet Protocol is a communications protocol that binds everything on the Internet. Along with a Ethernet communication cabling plant, it ensures that any building designed today will be ready for the Internet-based technologies of the future. This protocol is incorporated into the design of the building's infrastructure and permits communication between systems not only locally, within the building, but also over the Internet. It is especially desirable when dealing with multiple facilities. TCP/IP will allow for the facility to take advantage of all new developments occurring in research and web-based technology.
The final step in implementing integration is to create a testing protocol to ensure that all systems slated for integration are functioning as intended within the environment. Written documentation should be developed to set procedures for testing, commissioning and project closeout once the integration has occurred, and a training program should be established for all operating personnel.
The ultimate objective is to create paperless systems for the hospitals of the future. All building systems will communicate seamlessly with the building control system. Control of systems will pass from facility managers to the hospital's information technology group.
In the past, each system in a facility operated on its own network, but building automation engineers are now designing these systems around the structured cable plant used for communications. Thus, rather than using dedicated wires, each system will be able to tap into the network already installed and operated by the IT group.
Opportunities for system automation integration can be designed into new buildings or retrofit into older ones, taking into account the age of existing equipment and calculating the cost-benefit ratio. In considering systems integration, a facility should always think in terms of installing a system with a long life. The infrastructure of the communication path should have the capability for intercommunication that will allow it to take advantage of cutting edge technology, even if a facility's current equipment is less advanced. Since healthcare facilities must remain alert to productivity and operating costs, each investment must have value for the future.
Carlos Petty is a Associate Partner and Group Manager in the New York City office of Syska Hennessy Group, a consulting, engineering, technology and construction firm that provides technical solutions in such areas as building automation system design, facilities management, energy management, life safety, technology consulting/engineering, and turnkey design/build services.