We live in a world that relies on various wireless technologies to communicate with one another. For the general consumer, infrastructure elements such as strong cellular, radio, and Wi-Fi signals have moved beyond being a luxury into a matter of safety and security. Radio and cellular signals are often weakened in large buildings and other venues due to a variety of factors, such as radio frequency interference, low-emissivity glass, concrete, and other building materials. These obstacles create areas within the structure that have little-to-no signal, rendering radios and cellular phones useless. Not only is this a source of frustration for building occupants, but it also interferes with the communication of first responders in cases of emergency. However, there are ways to mitigate these issues. Distributed Antenna Systems (DAS) improve connectivity for occupants, and newer building codes, such as Emergency Responder Radio Coverage (ERRC), address communication for Police, Fire, and other emergency personnel.
The History of DAS
A distributed antenna system, or DAS, is a dedicated antennae network that allows personal cellular signals to be sent and received within a building, hospital, hotel, or other large venues. It typically uses a carrier’s licensed frequencies and greatly improves voice and data connectivity for occupants inside these structures. Initially, cellular service was considered an exclusive agreement between the service provider and the properties that utilized their DAS frequencies. This was problematic for inhabitants that used a different provider, as they did not have access to a signal strong enough to provide reliable service. Another concern for those who lived or worked in taller buildings was that cellular signals weaken as the distance between a user and the signal increases. However, the evolution of these systems has made them more streamlined, allowing demarcation points to shift from property lines and MDF rooms to individual offices and/or units, thereby strengthening connectivity. Best practices for effective DAS design and application have been set forth by the Building Industry Consulting Services International (BICSI) and the Telecommunications Industry Association. DAS requirements remain stringent for government buildings and hotels; however multi-family Owners and Developers are able to utilize alternative methods, such as Wi-Fi and Emergency Responder Radio Coverage (ERRC), to maintain adequate signal strength to ensure safety of building tenants and staff.
DAS and Wi-Fi
Innovations in wireless technology have allowed Wi-Fi to add additional communication options to the architecture, engineering, and construction industries. It’s becoming an increasingly popular alternative to trusting cellular networks alone and can usually be found in common areas of multifamily properties, college campuses, as well as conference rooms and offices. While Wi-Fi is a viable alternative to cellular signals, it can still fail if a user’s signal is weak. That failure can quickly become dangerous if that user is a first responder. In 2018, new requirements were initiated to strengthen wireless connectivity inside buildings, ensuring that communication would be available when wanted and, more importantly, when needed.
The Rise of ERRC
Emergency Responder Radio Coverage (ERRC) refers to the code requirements surrounding radio strength within a building. It is similar to DAS but utilizes different frequencies and legalities. Its main purpose is to help firefighters, police officers, and paramedics establish points of operation and communication, allowing them to respond to emergencies within buildings. While it is possible to use ERRC in place of a DAS or Wi-Fi connectivity, it is inadvisable to do so. ERRC is intended to run on one antenna using one frequency. Adding additional frequencies for non-emergency communication is cost-prohibitive, making a DAS or Wi-Fi a better option for everyday communication.
Before ERRC was developed, emergency personnel often wasted valuable time and resources finding an outdoor location with a signal strong enough to support their radio communication both inside and outside a given building. ERRC not only regulates the signal strength, it includes software with graphics for police, firefighters, and medics to track and monitor where personnel are located while onsite. However, despite these valuable benefits to first responders, these types of systems present specific design challenges that are best piloted by Federal Communications Commission (FCC)-licensed partners both because of their cost and safety implications.
Equipment needs for adequate service can vary because the strength of a signal inside a building can differ based on a number of factors, including what the building is made from or its proximity to a cell tower. Some projects may not need any additional equipment to boost signal strength. Other projects located in areas where cell towers are less prevalent or perhaps made from different building materials might require a more detailed system to support a signal strong enough for the safety of occupants and first responders. Also, installation costs can vary by manufacturer and location, potentially resulting in higher-than-expected initial expenses.
Code Updates and Their Impact
The importance of improving indoor connectivity for first responders came to light after the release of the Post-9/11 Commission Report in 2005. Before this, fire fighters relied upon phone jacks installed near stairways for communication indoors with personnel in the building’s fire control room. While having adequate radio signals indoors renders the jacks unnecessary, building codes still require them to be installed unless exempted by the respective fire marshal. In many cases, fire marshals need to be educated on ERRC applications and prevalence in contrast to what has been done in the past.
Subsequent building code updates have been enacted to ensure proper indoor signal strength for both new and existing buildings. While these new codes are determined by authorities having jurisdiction (AHJ) and can sometimes be county-driven, fire code officials are in charge of approving the system and frequencies. An FCC-issued General Radio Operator’s License (GROL) is required, as well as training and OEM Certification or skill satisfactory to the AHJ. Emergency generators need two hours of battery backup under this updated code, and if there is no emergency generator, 12 hours of battery backup are required. There are also minimum requirements for inbound and outbound signals’ delivered audio quality.
In the most recent version of the IFC code, signal boosters and system monitoring protocols were revised, including:
- Battery systems for emergency power must be housed in NEMA 3R cabinets.
- Any donor antenna must be isolated from interior antennae no less than 20dB greater than the system gain under all operating conditions.
- Installing system amplifiers, or any system that might interfere with an ERRC system, must be coordinated and approved by the fire code official.
- ERRC systems must be monitored by a fire alarm control unit or sound an audible alarm, as approved by a fire code official.
- There should also be automatic signals for any of the following: loss of AC power supply, battery charge and RF-emitting device failures, antenna malfunctions, failure of critical system components, and for communication links between the fire alarm system and the emergency responder radio enhancement system.
In regard to existing buildings without an approved communication system, one can be installed within a timeframe established by the AHJ. While it’s the building Owner’s responsibility to adhere to the code and meet annual recertification requirements, project partners can provide plans to help meet code requirements. System integrators must design and install ERRC systems using FCC-certified equipment in NEMA-4 enclosures. Signal testing falls under the responsibility of the Owner, integrator, and often the third party and is required to be completed annually.
According to the current code, a building’s ERRC system must cover at least 95% of public safety frequencies, and contractors that provide the designs and installation of ERRC systems must be licensed by the FCC.
The Cost of Lacking Coverage
ERRC and DAS can be retroactively implemented for existing buildings; however, the time, resources, and coordination to do so can complicate the process for many Owners and Developers. Fire marshals can bring a project to a halt during the final stages if signal strength standards are not fully met. If you leave these systems out of the planning and design phases of a project, one risks incurring additional expenses and subsequently rushing other phases of construction to stay on task. Retrofitting ERRC and DAS systems during or after construction often results in higher rates from project partners, due to an increase in the amount of coordination and materials needed to modify signal strength and coverage. For example, cables for emergency generators typically cost less than one dollar, but the price can rise to six times that amount for out-of-sequence system construction. In the near future, building codes will require annual signal strength testing, which will shrink the margin of error for system planning and implementation. When this update takes effect, it is best addressed by seasoned partners who can expertly plan and design communication systems, as well as coordinate signal strength testing efficiently.
DAS and Wi-Fi connectivity are highly technical systems and require experienced project partners to ensure that best practices are being adhered to. ERRC systems for emergency responders require coordination with FCC-licensed partners, code compliance, and extraordinary attention to detail.