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Guidance for Planning, Design, and Operations of Airport Communications Centers (2018)

Chapter: Section 5 - Communications Center Design Concepts

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Suggested Citation:"Section 5 - Communications Center Design Concepts." National Academies of Sciences, Engineering, and Medicine. 2018. Guidance for Planning, Design, and Operations of Airport Communications Centers. Washington, DC: The National Academies Press. doi: 10.17226/24980.
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Suggested Citation:"Section 5 - Communications Center Design Concepts." National Academies of Sciences, Engineering, and Medicine. 2018. Guidance for Planning, Design, and Operations of Airport Communications Centers. Washington, DC: The National Academies Press. doi: 10.17226/24980.
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Suggested Citation:"Section 5 - Communications Center Design Concepts." National Academies of Sciences, Engineering, and Medicine. 2018. Guidance for Planning, Design, and Operations of Airport Communications Centers. Washington, DC: The National Academies Press. doi: 10.17226/24980.
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Suggested Citation:"Section 5 - Communications Center Design Concepts." National Academies of Sciences, Engineering, and Medicine. 2018. Guidance for Planning, Design, and Operations of Airport Communications Centers. Washington, DC: The National Academies Press. doi: 10.17226/24980.
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Suggested Citation:"Section 5 - Communications Center Design Concepts." National Academies of Sciences, Engineering, and Medicine. 2018. Guidance for Planning, Design, and Operations of Airport Communications Centers. Washington, DC: The National Academies Press. doi: 10.17226/24980.
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Suggested Citation:"Section 5 - Communications Center Design Concepts." National Academies of Sciences, Engineering, and Medicine. 2018. Guidance for Planning, Design, and Operations of Airport Communications Centers. Washington, DC: The National Academies Press. doi: 10.17226/24980.
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Suggested Citation:"Section 5 - Communications Center Design Concepts." National Academies of Sciences, Engineering, and Medicine. 2018. Guidance for Planning, Design, and Operations of Airport Communications Centers. Washington, DC: The National Academies Press. doi: 10.17226/24980.
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Suggested Citation:"Section 5 - Communications Center Design Concepts." National Academies of Sciences, Engineering, and Medicine. 2018. Guidance for Planning, Design, and Operations of Airport Communications Centers. Washington, DC: The National Academies Press. doi: 10.17226/24980.
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Suggested Citation:"Section 5 - Communications Center Design Concepts." National Academies of Sciences, Engineering, and Medicine. 2018. Guidance for Planning, Design, and Operations of Airport Communications Centers. Washington, DC: The National Academies Press. doi: 10.17226/24980.
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Suggested Citation:"Section 5 - Communications Center Design Concepts." National Academies of Sciences, Engineering, and Medicine. 2018. Guidance for Planning, Design, and Operations of Airport Communications Centers. Washington, DC: The National Academies Press. doi: 10.17226/24980.
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Suggested Citation:"Section 5 - Communications Center Design Concepts." National Academies of Sciences, Engineering, and Medicine. 2018. Guidance for Planning, Design, and Operations of Airport Communications Centers. Washington, DC: The National Academies Press. doi: 10.17226/24980.
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Suggested Citation:"Section 5 - Communications Center Design Concepts." National Academies of Sciences, Engineering, and Medicine. 2018. Guidance for Planning, Design, and Operations of Airport Communications Centers. Washington, DC: The National Academies Press. doi: 10.17226/24980.
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Suggested Citation:"Section 5 - Communications Center Design Concepts." National Academies of Sciences, Engineering, and Medicine. 2018. Guidance for Planning, Design, and Operations of Airport Communications Centers. Washington, DC: The National Academies Press. doi: 10.17226/24980.
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Suggested Citation:"Section 5 - Communications Center Design Concepts." National Academies of Sciences, Engineering, and Medicine. 2018. Guidance for Planning, Design, and Operations of Airport Communications Centers. Washington, DC: The National Academies Press. doi: 10.17226/24980.
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Suggested Citation:"Section 5 - Communications Center Design Concepts." National Academies of Sciences, Engineering, and Medicine. 2018. Guidance for Planning, Design, and Operations of Airport Communications Centers. Washington, DC: The National Academies Press. doi: 10.17226/24980.
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Suggested Citation:"Section 5 - Communications Center Design Concepts." National Academies of Sciences, Engineering, and Medicine. 2018. Guidance for Planning, Design, and Operations of Airport Communications Centers. Washington, DC: The National Academies Press. doi: 10.17226/24980.
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Suggested Citation:"Section 5 - Communications Center Design Concepts." National Academies of Sciences, Engineering, and Medicine. 2018. Guidance for Planning, Design, and Operations of Airport Communications Centers. Washington, DC: The National Academies Press. doi: 10.17226/24980.
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Suggested Citation:"Section 5 - Communications Center Design Concepts." National Academies of Sciences, Engineering, and Medicine. 2018. Guidance for Planning, Design, and Operations of Airport Communications Centers. Washington, DC: The National Academies Press. doi: 10.17226/24980.
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54 S E C T I O N 5 Simple ACCs have a history dating back to the early part of the 20th century when air- ports started to become common throughout the world. During the early days of aviation, technology tools were relatively few—most airports’ communication technology toolkit consisted only of radios and telephones and airport staff typically had direct visual contact with passengers, aircraft, and airport facilities. As electronic security and operational sys- tems were adopted, airport security and operations staff migrated to a simplified version of what we now call an ACC, and operators were increasingly removed from direct visual contact with the operational environment. Although new technology tools provided greater functionality, they also removed the intuitive nature of direct observation and replaced it with information provided through electronic systems. Rather than being able to see actual conditions, staff was now required to visualize conditions through the “lens” of the systems they operated. Today’s ACC is technologically different from its predecessor—Operators have access to various technologies via computer interface, large-format video displays are common, and bulky consoles have been replaced by thinner, more streamlined consoles and electronic devices. More information is exchanged rapidly via electronic means, and multiple sites are connected electronically. Although these new technologies provide more capabilities, the increases in number of systems, size and complexity of today’s airports, and pace of technol- ogy evolution all challenge ACC staff to expand their grasp of information absorption and situational awareness. The ACC Design Phase translates the goals expressed in the CONOPS as defined by user requirements and subsequently refined in the planning documents into an organizational architecture composed of processes, procedures, functions, hardware, software, infrastructure, and facilities. Effective ACC design requires a balance of form and function. For an ACC, function tends to dominate—defining everything from the supporting spaces and infrastructure to the requirements of the engineered systems (e.g., mechanical, electrical, and fire protection). Depending on the functionality, ACCs may have the same needs as major data centers in regard to reliability and redundancy of heating, cooling, and power. The physical form of the ACC is almost as important as the activity being carried out. As with most specialized facilities, characteristics unique to the space must be accounted for in the design. Such characteristics include issues such as sightlines and lighting and a comfort- able physical environment designed to support collaboration without distractions in the workspace. Communications Center Design Concepts

Communications Center Design Concepts 55 5.1 A User-Centric Approach to Human Factors (HF) Design To ensure that human factors are sufficiently addressed in ACC design and operation, it is helpful to consider the perspective of the users in terms of the following four key elements of the user experience: • Access to Information. All users in the ACC need access to a wide array of information to perform their jobs. The source and types of information may vary widely, depending on the person’s role in the ACC, but such access is always necessary. Information may come from various sources (including both fixed and portable technology systems, individual or corpo- rate stakeholders, news feeds, government entities, and personal observations) and can be delivered via visual displays, audio, paper, or interpersonal communication. • Technology Tools. The various technology tools in use each have HF aspects that significantly affect user efficiency and effectiveness. • Interpersonal Collaboration. People must be able to interact effectively with one another within the ACC to achieve results. Many factors—technologies, space layout, organizational structures, personalities, and organizational cultures—affect interpersonal collaboration. • The Physical Environment. The space layout, environmental aspects (e.g., heating, cooling, lighting, and noise control), consoles, seats and furniture, and other physical characteristics all significantly affect users. These four elements relate to three zones: • The user’s immediate environment: This includes the equipment the user is operating, desks or consoles, seating, and people next to them. This zone has the greatest effect on the user and requires significant effort to ensure that it is conducive to a positive user experience. • Within the ACC: The next zone is the ACC environment just outside the immediate zone and includes the rest of the ACC environment. Although the user may not inhabit or interact with the rest of the ACC as much as their immediate zone, the user is affected by the space layout, location of staff, placement of large video displays, and other aspects of the overall ACC design. • Remote: Although not in the ACC, the user interacts with people, technology, information, and physical spaces in remote locations. Success in the design phase is dependent on engaging an architectural and engineering team that is aware of the functional issues and requirements of the space and capable of driving a design that supports these without sacrificing architectural amenities or good, comfortable space design. Further information on Facility Space Requirements and Layouts (Section 5.6), Ergonomics and Equipment, such as acoustics and lighting (Section 5.7), and incorporating Human Design Factors (Section 5.8) is presented below. 5.2 Human Factors Challenges in Information Absorption Although there has been significant technological innovation in recent decades, much of the human activity in ACCs today remains focused on tasks that have not fundamentally changed since the 1960s: • Operation of equipment at consoles or desks. • Telephone operation. • Interpersonal contact between individuals at their working posts, in meetings, and so forth. • Operation of video management systems and use of large-format visual displays.

56 Guidance for Planning, Design, and Operations of Airport Communications Centers • Printing, distribution, management, and storage of paper. • Maintaining normal operations during unusual events. Nevertheless, the challenges to information absorption and situational awareness caused by these activities have increased significantly as the number of systems that achieve these tasks has increased substantially and the speed with which they deliver information has grown pro- portionally greater. Factors that contribute to human fatigue and reduced performance include the following: • Equipment. The quality and performance of the equipment the operator uses significantly affect information absorption and situational awareness. For example, if electronic systems are poorly designed and difficult to use, or perform sluggishly, information absorption and situational awareness will suffer. Poor-quality computer monitors may prevent operators from fully comprehending information and can cause eye strain. • Access to Information. For operators to perform at peak efficiency, they need appropri- ate information delivered in a timely fashion. Information starts the operators’ workflow; when high-quality information is not available, information absorption and situational awareness suffer. • People. Operators need to interact with other staff in the ACC as well as with technology systems. If interaction is difficult because of poor space layout, inadequate electronic com- munications, or other data sharing factors, information absorption and situational awareness will suffer. • Environment. The ACC needs to be designed to be conducive to ACC activities and staff. Strict control of temperature, lighting, noise interference, and other factors can produce an environment that fosters effective information absorption and situational awareness. • Stress. The high-stress nature of the ACC environment, which includes critical situations requiring fast and effective action, can cause mental fatigue, thereby lowering information absorption and situational awareness. Long hours working at consoles can stress the human body, thus lowering information absorption and situational awareness. As technology continues to rapidly evolve, remember that technology is only a tool and peo- ple should remain the primary focus of the design and operation of ACCs. Application of an HF approach to communication and command and control center planning and design helps ensure the operator remains the primary focus. This user-centric focus on the requirements of the operator should result in greater operational efficiency and effectiveness. Human factors orientation requires a multi-dimensional approach to integrating people, processes, and technology. All aspects of the physical and logical environment need to be con- sidered. Moreover, the introduction of new technologies should be iterative, simultaneously aligning with and influencing people and processes. As people and processes interact with new technology, work capacity and efficiency should increase, thus allowing for changes in process and staffing, and ultimately laying the basis for the introduction of new technology as the cycle repeats itself. 5.3 Location and Physical Components of an ACC The last of the six “who”, “what”, “why” . . . questions is “where” and it is answered in the design phase. The answer to the “where” question depends on whether the ACC going to be a newly constructed facility or incorporated into an existing structure. Answering this question becomes more complex when the special considerations of an ACC are contemplated, such as • The relationship to the airport’s technology infrastructure—both primary and redundant. • The need/desirability to have access to the airfield.

Communications Center Design Concepts 57 • For locations with the potential for natural disasters (e.g., earthquakes or hurricanes), its ability to withstand those natural events. • Clean and uninterrupted power, with acceptable backup power. • Suitability of space (e.g., size, Americans with Disabilities Act [ADA] requirements, and envi- ronmental considerations). • Funding availability. The proposed location should also be discussed in terms of longevity. For example, an interim facility may be desirable while the airport plans for a permanent location. When determining the location, the following factors should be considered: • Geographic location is extremely important. Assess the geographical threat profile using data from FEMA and other sources to evaluate the possibility of threats (e.g., flooding and storms). An ACC facility should not be next to inherently risky areas (e.g., loading docks or parking structures). • Locating the ACC facility within a terminal or other building with public access can sig- nificantly impair survivability, cost, and usability. If possible, locate the ACC where it has the most physical protection from threats. In a basement or ground floor, the facility may be subject to flooding, while the highest floor of a building could be affected by storms or high winds. Avoid exterior walls and windows because of projectiles or explosions. If an exterior wall or window cannot be avoided, use wall-reinforcing techniques or window blast curtains. • An ACC facility will require a data center and/or a network operations center (NOC) that provide large-capacity utilities (e.g., power and cooling). Although the data center need not be immediately next to the ACC facility, greater distance creates greater costs for network and cabling connectivity and greater possibility of disruption. • Consider co-locating multiple ACC facility elements to leverage infrastructure and reduce overall cost. Having an EOC next to an AOC/SOC can provide definite advantages during emergencies. – Choose a site that has easy access during emergencies. Consider the difficulty of gaining access to ACCs inside the airport when the perimeter becomes locked down during emer- gencies. Those needing access may include first responders, outside staff, and parking and logistical space staff. – Plan for logistical support. During emergencies, it is common for staff to occupy the Com- mand and Control Facility for long periods of time. This may require food and water sup- plies and added computer or communications equipment. Ensure there is adequate power; IT bandwidth; space; access for deliveries and people; and, possibly, cooking, sleeping, and bathing facilities. • Ensuring survivability of systems in the event of system crashes, extreme weather, accident, or deliberate attack requires a structured approach to ensure the appropriate balance between robustness and cost control. To find the best balance, perform threat assessments (both physical and cyber) to determine the threat landscape and likely threats. • An additional consideration is the location of a backup facility, should the primary ACC expe- rience a catastrophic failure that renders it unavailable. Section 8.8 discusses considerations in developing a backup ACC. Examples of threats that may be encountered include the following: • Regional threats—weather, earthquakes, floods, population unrest, and other factors unique to the area where the ACC is located. Mitigation strategies include site selection to minimize threat exposure, facility hardening, and use of intelligence services and cooperation with local law enforcement to stay informed of emerging threats.

58 Guidance for Planning, Design, and Operations of Airport Communications Centers • Site threats—local utility grid reliability, nearby dangers (such as chemical plants and flam- mable materials next to the ACC). • Facility threats—structural integrity, perimeter security, and equipment reliability. The facility in which the ACC resides is an important part of survivability and deserves sig- nificant attention early in the design process. The ideal scenario is a robust structure capable of withstanding severe weather and some level of blast resistance. However, financial realities typically dictate that the ACC will be within an existing airport structure that may not have been designed with robust survivability in mind. When locating the ACC within an existing structure, be careful of threats imposed by the structure itself. For example, although basement space may be readily available and economical, it poses risks of flooding. Locations next to windows or on the top floor of a structure are subject to risks from storms or blast. The infrastructure of an ACC facility, although similar to those of commercial buildings, diverges significantly in a design process that determines adequate physical capacities, opera- tional capabilities, and other attributes. Basic physical components of an ACC are • The electrical infrastructure should have adequate capacity and conditioned backup power. Space for a generator should be allocated outside the facility, while space for an Uninter- ruptible Power Supply (UPS) and electrical switchgear should be allocated inside the facility. If possible, use a dual-fuel generator to provide greater alternatives for fuel sources during emergencies. When sizing the generator, the general rules used in normal commercial facili- ties (where the generator is usually sized only for the minimum capacity to facilitate evacu- ation of the building) do not apply to ACC facilities. Plan for extended operation using only generator power, and size the generator to support all the key systems that will be required (including HVAC and servers). The ACC should be able to operate even when local utilities are non-existent. • Heating, ventilation, and air conditioning (HVAC) will be one of the key needs for the ACC due to the number of electronic components contained within. Because HVAC is one of the costliest elements to retrofit after construction is completed, it is better to slightly overdesign (to accommodate future expansion) than to underdesign and lose that flexibility. Further, consider systems that provide positive air pressure if smoke or other air contamination may be an issue. • Structural attributes such as blast protection, high wind resistance, or earthquake criteria should be considered when designing new structures. When retrofitting existing structures, blast netting and other accommodations should be used. • Network/Internet access should be available from multiple sources to provide redundancy. Check with telephone carriers about the availability of dual, spatially separated feeds to the facility. Check with Internet Service Providers to secure connections from multiple sources, including possible satellite connectivity as a backup. • Envelope electromagnetic/lightning protection should be part of the design, and shielding from electromagnetic pulse (EMP) may be warranted in certain cases. • Wireless signal penetration is often an issue. Depending on the location, it may be desirable to enhance penetration of wireless signals from outside when they are part of your communi- cations network or to block them when signal interference is an issue. Wireless signals from cell phones, public safety radio systems, GPS, satellite, and other wireless communications should all be considered. To block wireless signals to prevent unauthorized communications, the use of a “Faraday Cage” technique is effective. By enclosing an area in a wire mesh, it is possible to block wireless signals. Wall coverings, ceiling tiles, and other building materials

Communications Center Design Concepts 59 with inherent wireless shielding are available. To enhance wireless reception inside the facility, wireless repeaters may be necessary when the building’s structure blocks signals. Multi-band repeaters that will work with all the wireless devices used should be considered. • Resupply and storage space for essential supplies, such as food, fuel for a generator, batteries, and office supplies, should be considered in the design. • Satellite dishes will require space on the roof and line-of-sight access to satellites. They will also need periodic maintenance. Plan roof layouts and access accordingly. 5.4 Basis of Design (BoD) The Project Management Plan explains the ideas, concepts, and criteria important to airport management and expressed in the project charter. The Basis of Design (BoD) documentation explains the processes and assumptions behind design decisions that are made to meet the design intent. The design intent evolves from more general descriptors to more specific descriptors during actual design, to in-depth and specific descriptors during the specifying stage. These last are finalized during the as-built phase. Under each area or building system is an outline of the building construction and operational requirements to meet the needs of the owner and the building occupants. The BoD document is a compilation of the specific criteria, codes, standards, guidelines, and specific project data and calculations that are the basic information that meets the own- er’s requirements. This information is used to develop the design and construction docu- ments. The BoD establishes the technical and facility requirements necessary to meet the CONOPS goals. The BoD is not a design itself, but a way for airport management and the ACC architect to define the parameters of the design by examining alternate ways of meeting functional require- ments. Each option is described in sufficient detail, including its advantages and disadvantages, along with estimated costs. A typical BoD document will include the following elements: • General facility description, including backup. • Facility location or a set of possible locations. • Space requirements and descriptions. • Adjacencies. • Regulatory and code requirements. • Requirements for redundancy, reliability, and recovery. • High-level descriptions of engineered systems (e.g., mechanical, electrical, and fire protection). • High-level descriptions of technology-based systems. Typically, the BoD will not describe operations and policies or procedures, although it will be influenced by these requirements. When the BoD has been completed, the design team will have a documented baseline of expectations and requirements from which to develop, design, and refine the facility and its supporting elements so as to produce documents suitable for construction. The BoD and the CONOPS must be synchronized to ensure that the functionality envisioned for the ACC in the CONOPS is reflected in the design documents. This synchronization is best achieved by the project manager of the ACC project and involves collaboration between the various entities participating on the project team throughout the design and construction effort. Although the CONOPS should be the guiding document, design constraints may affect

60 Guidance for Planning, Design, and Operations of Airport Communications Centers the CONOPS. In these cases, the project manager must elevate the issue to airport management, who must be included in decisions mitigating the effect or in revising the CONOPS. 5.5 Functional Design Objectives The design process should address the following performance and functional objectives and detail how such objectives are to be provided and validated: • Scalability. Scalability is a measure of the ease with which a facility, system, or elements of a system can be modified in size and capability to meet changing performance requirements. For an ACC, scalability means increasing the size of the facility as needs grow or expanding technology systems to support additional needs. • Reliability. Reliability refers to the ACC’s ability to continue to operate without a failure that compromises the integrity of the overall facility. Reliability is generally expressed as Mean-Time- Between-Failure (MTBF), which depends on equipment design and manufacturing processes. • Maintainability. Maintainability refers to the ACC’s ability to undergo normal preventive maintenance and corrective maintenance without the integrity of the overall system being compromised. Maintainability is generally expressed as Mean-Time-To-Repair, which is derived from equipment design and manufacturing processes. • Availability. Availability refers to the ACC’s ability to operate and perform normal functions, such as updates, backups, and recoveries, without compromising the integrity of the system. Availability extends Reliability and Maintainability to include equipment operation and duty cycle in the airport environment and the effects of operator training, support policies and programs (including servicing and spare parts replacement), and other factors that may not be intrinsic to equipment designed and manufacture, but affecting equipment performance. Availability also considers the redundancy of key systems, such as mechanical (cooling and heating), power (using normal/utility and emergency power sources), and networks and com- munications infrastructure. 5.6 Establishing the Design Process In planning facilities, recognizing the symbiotic relationship between design and construction is important. Design and construction processes are best viewed as an integrated system. Broadly speaking, design is creating the description of the ACC, usually represented by detailed plans and specifications, while construction planning is a process of identifying the activities and resources required to make the design a physical reality. Hence, construction is the implementation of a design envisioned by architects and engineers. In both design and construction, many inter- dependent tasks must be performed. In planning newly constructed ACCs, the following should be kept in mind from the beginning of the project: • Nearly every ACC is custom designed and constructed and needs an appropriate amount of time to complete. • Both the design and construction of a facility must satisfy the conditions peculiar to a specific site. • Because each project is site specific, its development is influenced by natural, logistical, and other locational conditions (e.g., access to the airfield and relationship to network and data center resources). • Given the long service life of an ACC, future requirements must be anticipated. • Because of technological complexity and new functions being added as the ACC concept evolves, changes of design plans during construction are not uncommon.

Communications Center Design Concepts 61 5.6.1 General Design Considerations In most ACC development processes, it may be necessary to use the services of a qualified design team composed of architects, engineers, and specialty consultants (possibly including audio/video designers, acoustical engineers, and lighting designers). Although many larger air- ports have internal resources with experience in some of these areas, few have extensive expe- rience designing these complete facilities. The components and requirements of ACCs are sufficiently complex and unique that specific expertise is essential. This is not to say that internal staff should not be engaged—architectural, engineering, and other design and operational professionals within the airport organization are the critical source of user requirements to the CONOPS and have the locally specific experience to offer significant support and historical perspective to the process. These individuals need to be involved from the early stages, as stakeholders, participants, and active contributors. In airports with existing ACCs (or similar centers), developing a new facility may result in out- ages and communication disruptions due to construction and cutover activities. Because many of the existing facilities support public safety operations, interruptions in service due to contractor activities must be prevented. During construction, all existing radio communications systems, telephone systems, and computer systems should remain fully operational during the installa- tion of the new system and until acceptance of the system by airport management. Where inter- ruptions in service are deemed necessary, coordination and communication among the parties is essential, and planning for alternate means of maintaining service must be developed. Finally, developing a new ACC does not happen in isolation. The new facility may be devel- oped over a multi-year period, often within a new or existing facility upgrade; therefore, it must integrate with existing or upgraded infrastructure. Coordination with other airport projects to avoid conflicts or unnecessary duplication of effort is essential and can prevent or mitigate issues such as inadequate power, conflicts for contractor access or logistical spaces, and integration issues due to network or other airport technology systems. 5.6.2 Using 3-D Modeling in ACC Design The use of 3-D modeling is invaluable in visualizing the finished ACC before construction begins. Although floor plans are sufficient to understand space layouts, they cannot convey the full experience of being “inside” a 3-D virtual model. Being able to “walk” through the space, “sit” in the seats, and see exactly what people will see inside the ACC is extremely valuable. 3-D modeling can also show design flaws not visible in floor plans. In one recent example, a large emergency management agency facility’s large-format video displays were originally designed to be mounted on the 40-ft-high walls of a huge room. A review of the design using a 3-D digital model of the space examined the sightlines and allowed “inhabiting” the virtual model and “sitting” in the virtual seats, which revealed that the placement on the walls was far too high to be usable. Catching this mistake before construction saved the client several hundred thousand dollars and prevented major time delays. 5.6.3 A Holistic Design Approach Technology is so interwoven in the fabric of the ACC that the design team should integrate architectural, engineering, human factors, and technology design into a single team. Although it is normally assumed that the design team will include architectural and engineering profession- als, the modern ACC is so complex that it warrants the involvement of additional professionals such as technology and human factors/ergonomics design specialists.

62 Guidance for Planning, Design, and Operations of Airport Communications Centers The technology and human factors/ergonomics designers should be involved from the begin- ning of the design process. Technology can affect architectural and engineering design significantly, sometimes in ways that only the technology designer can anticipate. Mistakes (e.g., undersizing technology spaces or HVAC capacity or putting consoles or video walls in the wrong places) can be costly to change later. Likewise, a human factors/ergonomics designer can influence the design in ways that may not be readily apparent to the other designers. Investing a small amount in these professionals initially will pay significant dividends in the end. 5.6.4 Accessibility as a Design Factor In addition to typical human factors concerns, the ACC must comply with the ADA and possibly other regulatory requirements, depending on individual staff members’ needs. Given that accessibility is a complex consideration, this Guidebook does not address details; however, ACC designers and managers should verify that basic ADA requirements are met and should determine if any staff require special accommodations due to disabilities. Some needs (such as those resulting from wheelchairs, braces, or crutches) are obvious, but not all disabilities are discernible. Human resources professionals should be involved so as to determine which staff have special needs. Challenges such as color blindness or hearing impairment may require special approaches above and beyond satisfying basic ADA requirements. For example, when there is a visual or hearing impairment, Section 508-compliant software can accommodate many needs (see http://www.section508.gov for more information). Keep visual and hear- ing impairments in mind when designing ACC equipment for communicating with the ACC staff (e.g., signage or video displays). For example, when color coding is used, add symbols to accommodate staff who are color blind. 5.7 Facility Space Requirements and Layouts In the optimum layout, system users should be arranged so that there is a balance of col- laboration and face-to-face communication, as well as a degree of privacy, isolation, and acoustic separation in performing activities. During day-to-day operations, certain events and the response to these events will call for console operators to consult with one another— this should be possible by turning in one’s seat to discuss a situation with an adjacent console operator. Space planning will need to address situations from accommodating immovable architectural obstructions to a free arrangement and ideal positioning of consoles, furniture, support hard- ware, and displays. The ceiling height and the beams in the ceiling directly affect how the space will be used, how the line of sight to shared displays will be accomplished, and how sounds will be perceived. It may be feasible to array consoles in an arc or circle, a cluster, or in a linear row- by-row fashion, providing adjacency for related functions. The following spaces typically are provided for airport ACCs: • Communication and dispatching operations areas. • EOC. • Break room/lounge area (with coffee machine, sink, microwave, dishwasher, and related facilities). • Kitchen and dining room. • Locker rooms. • Supervisor/management offices (to include computer access, telephones, radios, and faxes). • Storage rooms. • Space for bookshelves, file cabinets, printers, and fax machines.

Communications Center Design Concepts 63 • Conference rooms. • Server/Network Operation Center (NOC). Certain work groups benefit from an arrangement where everyone is facing a common central node or perhaps a center supervisor console. Other arrangements seek to reduce, as much as possible, the interaction with other console operators. In a public safety dispatch environment, a design that encourages interaction between dispatchers is usually preferred—The face-to-face collaboration between the dispatchers during peak periods or major incidents can be an invalu- able benefit of proper console arrangement. The overall look and feel of the space should be designed to be soft and subdued, using neu- tral colors and hues. Neutral tones allow displayed video and graphics to portray skin tones and other hues more accurately than if bright colors are anywhere near the field of view. Lighting should be subdued to reduce eyestrain during prolonged operations. Chairs are critical to users’ comfort, and the best possible ergonomically correct seating should be adopted for consoles. Absorptive materials on walls and in ceilings soften the acoustical environment and reduce stress and reverberation because they reduce noise bounced off hard surfaces and help to isolate the voice of a speaker within the console area. 5.7.1 Console Layout Console positioning significantly affects many aspects of ACC operation and user experience. Rather than using classroom-style rows, many airports use console configurations that support work groups—for example, small, communal tables are placed next to work groups to provide “mini-conference rooms,” thereby allowing collaboration without leaving the ACC. 5.7.2 Staff Grouping Assessing how people interact with one other and the layout of the space are important for opti- mal interpersonal efficiency. Grouping staff by functional area promotes efficiency, allowing staff who need to work together to collaborate without excessive movement or disrupting other staff. It may be necessary to separate some groups from one another to reduce noise transmission. For example, staff working in an EOC during an emergency may generate considerable noise, which would disturb operators answering 911 calls or maintaining normal operations. Glass partitions separate while maintaining visual connectivity among groups and among video displays. 5.7.3 Sightlines Ensure that staff have access to the visual resources they require (e.g., video walls and other large-format visual displays). Ensure that managers have unobstructed sightlines to staff they need to communicate with (a gesture or facial expression can be extremely valuable in com- municating during an emergency). At a minimum, perform sightline studies and conventional renderings, and, if possible, use 3-D digital models. 5.7.4 Adjacent Conference Areas and Executive Spaces Spaces next to the ACC, but not inside it, allow executive meetings without disturbing ACC operations. Some airports locate these spaces next to the ACC with a window or sliding glass door between the spaces. This allows a visual connection between the spaces, making better use of large-format video displays and allowing non-verbal visual communication. To ensure that occupants of these spaces can communicate with the rest of the ACC when necessary, audio intercoms should provide connectivity to the ACC operators as well as any other nearby spaces.

64 Guidance for Planning, Design, and Operations of Airport Communications Centers 5.7.5 Support Spaces Restrooms, locker rooms, and break rooms must be adequately sized and close enough to limit walking time spent between the ACC and support spaces. Support spaces must also provide “sensory buffers” from ACC activity, so that workers can de-stress in quiet, restful environ- ments. Some forward-thinking ACCs install reclining chairs so that staff can relax during breaks. 5.7.6 Positioning of Shared Equipment Printers, scanners, fax machines, and other shared equipment should be placed so as to mini- mize walking time from the ACC. Some ACCs locate printers inside the ACC next to workers; however, printers create noise and produce environmental contaminants (e.g., toner fumes and paper dust that can cause worker discomfort and sometimes trigger allergic reactions). 5.8 Ergonomics and Equipment ACC consoles should enable calltakers and dispatchers to work quietly and efficiently, using ergonomic interfaces. Storage space for reference material should be provided at each console position. Consoles should support all voice and data functions of the ACC without distracting interference. Personnel should be able to stand or sit and to adjust the lighting on their consoles. See Section 5.7.1, Lighting, for detailed information. ACC console position configuration will depend on several factors, including the focus of the facility (e.g., general communications versus security operations or emergency dispatch) and the operational philosophy of the facility as well as, to some degree, the flexibility to accommodate individual operators (e.g., disabled or physically large or small). Although some positions may serve only one specific purpose or handle multiple ACC roles, most will rotate among persons with unique physical characteristics. This variability in demand can drive the size and fit-out of consoles and furniture, as well as the scale of the technology procurement and build and the bal- ance between operational needs, cost, and support requirements. The range of services that can be provided from a single position includes • Interface with airport public safety radio systems (including trunked radio systems) to com- municate with units in the field and police, fire, operations, maintenance, mutual aid and Enhanced 911 calls. • Instantaneous playback of radio and telephone conversations and video incident streams. • Voice telephony, both external and internal to the airport, provided by a commercial carrier and IP-based, networked voice telephony. • Access to a dynamic mapping/location system integrated with the access control and video surveillance systems, with the ability to monitor incidents in real time. • Access to audio for the TV monitors via non-priority audio channels in the dispatchers headsets. • CAD capability. • Networked displays on operator workstations and video walls, if used. • Internet access for personnel via a separate standalone computer and separate network. • Monitoring and control of fire alarms. • Control of vehicle and personnel access gates. • Passenger screening entry and duress alarms. • Access to parking garage intercom. • Access to airport shuttle bus intercom. • FAA crash phones. • Individual workstation controls for task lighting, climate, and console positioning.

Communications Center Design Concepts 65 General office equipment and furniture in an ACC should include copiers, printers, facsimile equipment, bookshelves, work tables, and storage cabinets. Multiple handheld radio and cellular phone-charging stations should be provided in quantities appropriate to support multiple shifts of operators and observers. 5.8.1 Lighting Lighting is critical in creating an environment conducive to information absorption and situ- ational awareness. Lighting that is too bright or causes glare can seriously reduce information absorption and situational awareness and must be avoided. Overall lighting levels should be lower than in a normal office environment so as to enhance viewing of display screens. Typically, staff like windows, but windows can introduce lighting extremes that make control- ling light levels in the ACC difficult. When windows are present, the use of window tint film and/ or operable shades/blinds will allow adjustment to avoid lighting anomalies during daylight hours. Overhead lighting should be arranged so that it does not create glare on displays or glare directly visible by staff. When 2 × 4 florescent lights are used, use glare-reduction baffles; when using track lighting, be sure that fixtures are set deeply enough to hide the bulb from the direct sight of staff. Individual task lighting is also important, especially when overall lighting levels are low. Desk- mounted task light can be useful for reading or accessing items in drawers. Colored lighting schemes can be useful to alert ACC staff to unusual or elevated security conditions. Multiple-color fixtures placed where all staff can see them can be an inexpensive approach. More advanced systems allow lighting throughout the ACC to be altered from a single control position. Even more advanced systems can control lighting so that certain alarms/alerts trigger changes in lighting. 5.8.2 Acoustics Sound control is important to maintaining information absorption and situational aware- ness, especially in high-stress environments like ACCs that also experience emergency situa- tions. It is vitally important to control sound transmission in ACCs to prevent creation of an “echo chamber” that can quickly elevate sound levels so that staff have difficulty communicat- ing. Sound absorption techniques commonly used include sound-absorbing materials for walls, floors, and furniture, as well as limits in the use of hard surfaces like glass and tile. When sound issues are extreme or where it is not practical to replace wall, flooring, and fur- niture materials, electronic noise cancellation can significantly reduce extraneous noise. Basic electronic noise cancellation systems typically use speakers that generate “white noise,” which muffles noise. More advanced systems use active damping techniques and equipment to detect noise, analyze its waveform, and then electronically generate an “anti-noise” waveform that is the acoustic opposite of the noise. The two sounds cancel each other, thereby reducing noise. 5.8.3 Workstation Design and Seating Seating in ACCs is one of the most important and often overlooked aspects of human factors in ACCs. Quality seating minimizes stress and strain on ACC operators and enhances atten- tion, information absorption, and situational awareness. The Human Factors and Ergonomics Society ANSI/HFES 100-2007 recommends that seating conform to the following: • Has a lumbar support • Has a backrest that reclines

66 Guidance for Planning, Design, and Operations of Airport Communications Centers • Has a seat pan that adjusts for height and tilt • Supports at least one other seated reference posture in addition to the upright sitting posture • Provides support to the user’s back and thighs in the chosen reference postures • Can be adjusted to provide clearance under the work surface • Includes information for the user about the recommended use and adjustment of the chair One of the most innovative developments in console design is the ability to raise and lower the desktop, allowing operators to stand or sit as they want. Although it may seem counterintui- tive, staying seated for long periods is actually more stressful, both mentally and physically, than alternating between standing and sitting. The size and shape of the console is dependent on the activity of the staff member occupying the console and the size and shape of available space. PSAP/911 operator consoles in an ACC often use a “boomerang” shape that mounts screens and keyboard on a central section, with “wings” to the sides that keep other non-primary equip- ment within easy reach. ACC Consoles used for answering 911 calls are typically arranged without a central focal point, with attention given to avoiding distractions in the operator’s sightline and to providing ample space between operators for reduced noise. Airport EOCs often use a classroom-style orientation with a single focal point to enable staff to simultaneously view managers and visual resources (such as video walls), so that information can be quickly disseminated to the entire group at once. 5.9 Human Factors ACCs are complex high-stress environments composed of people, technology, and the physi- cal environment. Multiple departments, roles, and functions may operate simultaneously in the ACC (depending on its profile). Various technologies are used for management, security, and other functions. The environment itself (the physical space) is designed to facilitate efficient operation of the ACC. Activities in the ACC may deal with life safety and national security situations, requiring the ACC and its staff to operate at peak efficiency and effectiveness. One of the key aspects required to achieve a high level of efficiency and effectiveness is maintaining an environment conducive to information absorption and situational awareness. Operators must be able to digest, analyze, and act on information from a range of sources and to synthesize situational awareness from disparate sources of information. When designing and operating the ACC, it is important to understand the link between human factors and the ability to achieve conditions of information absorption and situational awareness. In high-stress environments like ACCs, every aspect of the environment affects the staff’s efficiency and effectiveness. Even minor aspects that cause distraction, inconvenience, or inefficiency to the staff are magnified in the often life-or-death situations that occur in ACCs and can hinder operations in significant ways. Proper ACC design enhances information absorption and situational awareness of staff; poor ACC design that does not appropriately address human factors will hinder information absorp- tion and situational awareness. To ensure the efficient operation of the ACC and information absorption and situational awareness, it is crucial to understand and optimize the human factors of the environment. Human factors can be defined as “the scientific discipline that studies how people interact with devices, products, and systems. It is an applied field where behavioral science, engineering,

Communications Center Design Concepts 67 and other disciplines come together to develop the principles that help assure that devices and systems are usable by the people who are meant to use them. The field approaches design with the “user” as its focal point.” Key aspects of human factors include • Acoustical design that establishes and maintains a calm environment. • Lighting design at individual stations and for the entire shared space. • Furniture comfort and efficiency, with an emphasis on ergonomic needs. • Good sightlines for shared resources and for inter-position communications. • ADA compliance. Review the ACC design and configuration examples for small, medium, and large airports and choose what is best for your local situation. Small airports often integrate their ACC-SOC-AOC- EOCs into one facility operating 24/7 or set up their EOC in an adjoining room for emergen- cies. Small ACCs often use wired telephony supplemented by trunked radio groups and cellular telephones for routine matters and emergency notification. Medium-sized airports often fully integrate their facilities to provide surveillance, alarm monitoring, police dispatch, and emer- gency response with cross-trained personnel 24/7. Large airports are usually integrated, but may segregate some functions while benefitting from shared facilities and cross-trained staff. CAD, access control monitoring, extensive surveillance systems and systems such as license plate recognition are more prevalent at large airports. International airports, regardless of size, are complicated by the addition of federal customs, law enforcement and immigration functions, and requirements for specialized facilities. Architectural approaches, such as glass walls/doors or movable walls, provide the flexibility to achieve collaboration without disruption. Interior glass walls or doors can also allow visual communications between personnel who staff ACC elements as well as enable the sharing of visual resources like video walls. Glass doors, however, can present dangerous projectiles if not appropriately isolated from blasts, so they should be built to standards for blast protection. • Consider ergonomics and human factors: A supportive human interface for each ACC operator is critical for effective performance, especially under stressful conditions. – Design with staff comfort in mind to reduce stress and improve performance. Be careful of lighting design to prevent glare. ACC facilities are not typical office environments, where lighting is often too bright. An ACC facility operator will be visually focused on computer screens and large-format video displays. – Design to manage sound. During emergencies, ACC facilities can be noisy due to the num- ber of people and the level of activity. Use techniques such as electronic sound masking and sound deadening materials to avoid aural overload. – Create effective sightlines. Provide the necessary visual resources, such as video walls and other large-format visual displays. Ensure that managers have unobstructed sightlines to communicate with staff (often, a gesture or facial expression can be a means of communi- cation in an emergency). At a minimum, do sightline studies and conventional renderings and, if possible, use 3D digital models. – Design appropriate seating. Ergonomic seating can increase attention spans and reduce repetitive strain injuries. Consider alternate desk and console designs. Newer desks, con- soles, and seating are designed to reduce fatigue and stress (e.g., consoles that are movable up and down allow staff to sit or stand). • Consider traffic patterns. Ensure that staff can move within the space without causing dis- ruption. Place resources such as copier machines where staff can easily access them without encroaching on others’ work spaces. • Design for flexibility during emergencies. The profile of the ACC facility changes during emer- gencies because Command and Control Facilities tend to become crowded when emergencies

68 Guidance for Planning, Design, and Operations of Airport Communications Centers occur. Flexible design elements (e.g., moving walls and sliding glass doors) allow easy recon- figuration as needed. • Plan for media access. Ensure the press area is segregated from the rest of the facility to prevent security breaches. (See Section 2.7 on establishing a Joint Information Center.) • Create Official Observer access. If space permits, build an observation area that enables visual and audio access to video walls and other communications. This should isolate sound from the main operational area so that observer discussions are not disruptive. Observer areas may also require escort services for visitors who are not badged for the area. 5.10 Current ACC Designs Because communications centers are unique in their individual physical and operational envi- ronments and, thus, do not follow a single well-defined pattern, it is not possible to provide an exact list of stakeholders, their functions, or their requirements. In addition, organizations with different priorities and administrative structures may take different approaches to engaging stakeholders, thereby including or excluding some additional players. Often, the timing may be driven by a need to meet regulatory, policy, or other procedural requirements, the nuances of which must be thoroughly understood as part of the driving force behind development. An example of this is a new or upgraded terminal expansion project that may cause a relocation of the existing communications center and/or create an opportunity to include a new facility within an unrelated capital project. The following examples reflect the site location and/or space the organization has available and provide a basis for identifying limits or constraints that can influence the design solution or are identified early as significant barriers to achieving the facility’s goals. Constraints (e.g., available space or location) can and should be raised early to identify alternatives and options if planned location(s) should become unsuitable or less than optimal (i.e., it may be more cost-effective to wait, if new capital projects are on the airport’s horizon). 5.11 ACC Examples ACCs come in all sizes and configurations—there is no single best design. The following are examples of ACC facilities in use at small and medium-sized airports. There is wide variation in functionality, design, and sizing; each ACC must be adjusted to local requirements and local budgets. Large or Category X airports have so many possible configurations that is not possible or even desirable to try and define a single example. 5.11.1 Small Airport Figure 5-1 shows an example of a small airport. This airport has built an integrated AOC-EOC facility. The Airport Police Department (APD) is located separately, close to the TSA checkpoint for response reasons. Next to the AOC is the EOC, a conference room equipped with a large table having both power and LAN outlets for participant laptop computers and large video screens to display activities at multiple sites. The ACC does not provide for operators to remain overnight during emergencies but has made arrangements with nearby hotels, should this become necessary. The same spaces used for the AOC and the EOC include offices for the Manager of Airport Operations, the Security Coordinator, and the two Operations Supervisors. Their locations pro- vide immediate access to the airfield, with equipped response vehicles parked at the exit portal.

Communications Center Design Concepts 69 Communications modes and technologies include • Wired telephony, which is the primary means of communicating with external parties. • Trunked radio talk groups, provided by the 800-MHz radio system of the city and used by the Operations, APD, and ARFF staff. • Cellular telephones, used by airport management, operations, and maintenance staff for routine activities and receiving alerts, including notifications of security breaches and emer- gency events. The airport has two cellular carriers that use different modulation schemes. The CDMA-based carrier primarily serves the airport management staff. The GSM-based carrier primarily serves operations and maintenance, and its service includes a push-to-talk party-line type radio mode, commonly known as Direct Connect, which is popular with maintenance personnel. • Standard VHF radios for airfield and ATC tower communications. • The terminal building is augmented with emergency generators providing power during out- ages for up to 3 days. Design criteria for data storage requirements are often driven by state law, which sometimes requires that all video imagery and voice messages recorded by a state agency be stored for a min- imum of 30 days and may require a minimum level of resolution for forensic review purposes. The airport in the above example has complex external communications because the airport property overlaps two counties and one City, so it must be able to communicate with multiple public safety (Sheriff and Police), fire, and EOC. Most such communications are done by wire telephony; the airport does not have dedicated fiber links to any external agencies. It does have priority access arrangements with its cellular carriers, but, in an areawide emergency, the airport is still vulnerable to the volume of public safety communications overloading cellular channel capacity. External communications requirements are set forth in the Airport Emergency Plan (AEP) and should be developed in the CONOPS for informing the ACC planning and design. Lessons learned from building and operating the integrated AOC-EOC at this airport include • Involve Operations, Police, IT, and other stakeholders early in the CONOPS and planning/design stages. • Locate the facility in a secure area, not in a public area, to avoid distractions. • Include break room and restroom amenities within the center to maximize staff comfort and reduce the need to leave the center. Figure 5-1. Example small airport.

70 Guidance for Planning, Design, and Operations of Airport Communications Centers • Co-locate Operations, Public Safety, and Security functions to the maximum extent possible. • Enable multiple ACC monitoring stations to perform all functions, including support of area- wide emergencies. • Locate Operations offices on a ground floor, inside the secure perimeter of the airport, with airside vehicles close by for ready access to the airfield. • Locate IT and communications equipment with the monitoring stations, including UPS backup, with central equipment and backup provided in a different location(s). • Cross train AOC station operators. • In future infrastructure planning and design, provide capacity for cable pathways to areas where additional functions might have to be provisioned. If fiber cabling is installed in these pathways, cable specifications should be compatible with the pathway design, including cable bend radii. • If a raised floor in and around the AOC is used for cabling and equipment, ensure that ample space is provided for easy installation, addition, maintenance, and replacement of power and data cabling vs. intra-wall fixed conduits. 5.11.2 Medium-Sized Airport Figure 5-2 shows a medium-sized airport’s approach. This airport has configured an inte- grated AOC-Police CAD-EOC, known as the AOC. It is within the APD, but this facility is sched- uled to be relocated under an announced construction program. As the design work progresses, beginning with the BoD phase, opportunities will arise to prepare an AOC-specific CONOPS. The AOC provides police dispatch, surveillance, and physical security monitoring, and emer- gency operations support functions, including response to physical attacks and natural disasters as set forth in the AEP. The AOC is staffed 24/7 by airport police and operations personnel. Within the AOC, the multiple stations are equally capable, and operating personnel are cross- trained for their functions to provide redundancy. The AOC is configured with a full set of communications modalities, including wired tele- phony, cellular telephony, 800-MHz trunked radio talk groups provided by the local county, and a LAN capable of carrying IP telephony. The airport uses the communications services of the County Sheriff’s Office. This consists of two 800-MHz Simulcast Systems and a Microwave System that connects 15 communica- tions sites throughout the county. The Mutual-Aid Conventional Simulcast System provides Figure 5-2. Example medium-sized airport.

Communications Center Design Concepts 71 countywide radio coverage on four mutual-aid channels using seven transmit/receive sites and two receive-only sites. Mobile and portable radios are also programmed with conventional talk-around channels used for car-to-car, portable-to-portable, and portable-to-mobile communications. Range is limited, but in an emergency, these channels could provide communications between units working an event. The Mutual-Aid Conventional (Talk-Around) Channels are programmed into every radio for interoperability between public safety agencies, including other counties and state agencies. External communications, as set forth in the AEP are the responsibility of this airport’s IT department in coordination with County Sheriff and Fire departments. The IT department pro- vides for redundancy and backup capabilities, with servers and UPS in the equipment room next to the AOC, additional UPS backup in central IT facilities, and engine-generator cutover from UPS units.

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TRB's Airport Cooperative Research Program (ACRP) Research Report 182: Guidance for Planning, Design, and Operations of Airport Communications Centers helps airports of all sizes determine which type of airport communications center best meets their operational needs. Various functions include dispatch of police, emergency response, maintenance requests, and monitoring of airport systems. In some cases, individual departments have “siloed” these functions into separate call centers. Myriad factors need to be addressed in considering the best approach to providing necessary airport services for employees and for the public.

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