Integrated Building Systems
The hope has been that new technology and management tools will make building system integration much more seamless. Are we there yet?
NFPA Journal®, November/December 2008
By J. Robert Boyer and Wayne D. Moore
We have all heard the question "Are we there yet?" when traveling with children or those acting like children, but it is a relevant question regarding integrated building systems. Automated systems such as HVAC, lighting, fire and life safety, security, energy distribution, and more recently, mass notification systems (MNS) are just a few of the independent systems found in buildings today. And although these systems typically work independently, a significant benefit can be achieved by coordinating control among them.
Even though building owners have been sold on the advantages of integrating their building systems over the last two decades, however, the installations have met with mixed results.
The reason for integrating building systems is the cost savings the owner gains from a more efficiently managed building. Typically, the management of the lighting and HVAC systems are the most often integrated building systems, but these can be interfaced with the management and billing of the tenant parking garage, building security, access control, and, of course, building emergency voice communications/alarm and MNS.
The underlying differentiator of the moderately successful to fully successful integrated building management system is usually the degree that the system is truly integrated versus just bundling dissimilar products and systems, which are then often interconnected into the base building management system via gateways.
Designing an integrated system
A truly integrated system uses a common software platform within an open system architecture using distributed logic. Every device used must be listed for each application and function to the most demanding level prescribed by the appropriate American National Standards Institute (ANSI) standard. This product examination is normally performed by a third-party, nationally recognized testing laboratory to ensure the suitability and compatibility of each component listed for its intended application in the system.
In the article "What to Look For in a Building Automation System," published on Buildings.com last January, author Steve Tom states that "it can be difficult to know what features you need, what system is best, or even what to ask system providers." In the specific area of life-safety systems, a key question is whether the fire alarm system can be integrated seamlessly with the building management system.
The most apparent reasons for the mixed results of these integrated building systems are poor planning during the design stage and a lack of coordination with the contractors installing each of the systems to be integrated. An additional issue is that the only system in the integration process that is regulated, and the one that can keep the building owner from getting an occupancy permit, is the fire alarm system. In addition, there is a fear among the fire official community that lack of maintenance or improper maintenance of the integrated building system will adversely affect the fire alarm system.
First, the design of the integrated building system is the hands of at least three engineering disciplines: electrical, mechanical, and fire protection. Each of these design disciplines must coordinate with the others, and all must understand the owner’s goals for the building systems integration plan.
The planning and design of an integrated life-safety system should employ a risk assessment methodology to determine the appropriate equipment, level of reliability, operational procedures, and personnel required to fulfill the owner’s objectives and code mandates. Establishing overall objectives that can be used in creating the design specifications and the operational procedures is important. The design professionals should be responsible for preparing the design specifications that will outline the emergency use objectives. The keystone for overall success is at the design and specification stage. Nowhere in the construction process can time be better invested than up front in developing and documenting a clear systems integration design and specification.
Basic integrated system requirements
The basic requirements for most building management systems are that they function as expected and are installed in accordance with NFPA 70®, National Electrical Code® (NEC®), and the codes affecting the integrated environmental and mechanical systems. The integration of the fire alarm systems with building management systems has been facilitated by changes made to NFPA 72®, National Fire Alarm Code®. Obviously, the goal of the code is to preserve the integrity and reliability of the fire alarm system.
The 2007 edition of NFPA 72 provides the requirements for integrating a fire alarm system into other building systems over a common pathway in Section 18.104.22.168 and Subsections 22.214.171.124.1 and 126.96.36.199.2. These requirements are significant because they allow a listed, non-fire alarm system to share signaling line circuits as long as the unlisted, nonfire alarm equipment meets the criteria outlined above.
In addition, the integrated building systems must meet the requirements of Section 6.8.4, "Combination Systems," and Subsections 188.8.131.52 through, and including, Subsection 184.108.40.206 of the 2007 edition of NFPA 72. This part of the code offers a variety of permissive requirements that enable fire alarm systems to become part of the integrated building systems design.
The fire official’s role in the integrated building systems approval is generally confined to the fire alarm system and how it is integrated with the building management system. Section 220.127.116.11 reads:
"18.104.22.168. If the authority having jurisdiction determines that the information being displayed or annunciated on a combination system is excessive and is causing confusion and delayed response to a fire emergency, the authority having jurisdiction shall be permitted to require that the display or annunciation of information for the fire alarm system be separate from, and have priority in accordance with 22.214.171.124, over information for the non-fire alarm systems."
The requirements of this section are important to the first responders’ ability to benefit from the information the fire alarm system provides in an emergency. They also give the fire official the authority to ensure fire-related information is not "lost" in the maze of other building management information given on the Command Center’s TV Monitors or the remote fire alarm annunciator.
It is imperative that the integration of the fire alarm system not be affected in any way by the other integrated systems. Many fire officials are concerned that someone making a program change to the operation of the building automation system will change the operation of the fire alarm system interface that is required to operate a fire-safety control function. For example, if the fire alarm system is designed to shut down the HVAC supply or return fans through the building automation system and a programmer working on the HVAC system operation makes a change to that operation, the fire alarm system interface may be affected. The technician working on the integrated building system will probably not be trained to install and maintain the fire alarm system. Nor will that technician be knowledgeable in the requirements of NFPA 72. And unless issues such as thes are addressed in a reliable way, fire officials will continue to be reluctant to approve the integration of the fire alarm system with other building systems.
In addition, they are concerned that, because the testing and maintenance of the fire alarm system is the only part of the integrated building system that is required by code, the owner will choose not to perform the required testing. The example used by most fire officials is that the building management system may develop problems that are expensive to repair, and the owner can choose not to repair the system. The owner is assuming that the worst outcome from the nonrepair will be environmental issues that can be dealt with when funds become available. In the meantime, the fire alarm system fire-safety control functions will be adversely affected.
The interconnection process
Once the requirements for the fire alarm system are met and the authority having jurisdiction has approved the integrated building systems approach, the designers must determine the appropriate protocol for interconnecting the different systems. Most building management systems use proprietary communications methods, such as BACnet and LonWorks. Fortunately, there is a growing trend toward using open, public standards, which will promote interoperability. Regardless of the advances in technology and interoperability of the equipment, however, better coordination of the subsystems must be developed.
In addition, design consideration should be given to minimizing critical wiring paths, equipment and wiring exposure to fire threats, and other physical attacks. The 2007 edition of NFPA 72 has specific requirements for the interface of fire-safety control functions, such as those found in Section 6.16, "Protected Premises Fire Safety Functions," which requires the fire-safety functions to not interfere with power for lighting or for operating elevators but does not preclude the combination of fire alarm services with other services requiring monitoring.
Additional requirements for integrating fire alarm systems with other systems include locating a listed relay or other listed appliance connected to the fire alarm system to initiate control of protected premises fire-safety functions within 1 meter (3 feet) of the controlled circuit or appliance, and monitoring the installation wiring integrity between the fire alarm control unit and the relay or other appliance, except those devices or appliances connected in a fail-safe mode. Interconnection methods between the fire alarm system and controlled electrical and mechanical systems must be monitored for integrity, comply with the applicable provisions of NEC Article 760, "Fire Alarm Systems," and be achieved by one of the following recognized means:
For more on NFPA 72 requirements, see sidebar.
As such, NFPA 72 provides guidance for circuit survivability that will meet the design goals for circuit robustness and reliability.
The goals of integration
The building owner’s expectation for an easy-to-operate, intuitive, seamless, quality integrated building system is within reach. However, much work is needed to ensure that each of the subsystems to be integrated into that system is installed correctly and that their installation is coordinated. An especially important aspect of the integration of the subsystems is how the fire alarm system will be integrated. In our opinion, after the design coordination has been accomplished, a single technical engineering coordinator is needed to help the subsystem contractors meet the goal of a truly integrated system as designed.
Originally the goal of integrating building systems cost-efficiently led mostly to a focus on environmental and security issues. After 9/11, owners and occupants realized they needed to reevaluate their integrated building system to ensure all building management systems operated as an integrated life-safety system. For example, NIST’s work in assessing the loss of the World Trade Center resulted in numerous recommendations to incorporate into new construction.
These are changing times. What was sufficient in the past no longer meets the needs of the present. Integrating life-safety communication systems with security and building control functions presents an expansive opportunity to provide superior life-safety protection and system utility while meeting the efficiencies and cost savings expected by the building owner.
So, "Are we there yet?" It appear we are still on the journey to our goal of effectively integrating all building systems and have not yet arrived at the point where the seamless operation of all integrated systems can take place reliably.
J. Robert Boyer is director of Industry Relations for GE Enterprise Solutions, Security. Wayne D. Moore is a principal with Hughes Associates and immediate past chair of the NFPA 72 Technical Correlating Committee.