How is it that Americans spend 88% or so of their day indoors but the de facto standard for designing cellular networks concentrates primarily on outdoor coverage?

The cottage business of installing cellular Distributed Antenna Systems (DAS) seeks to remedy deficient indoor coverage with various products and approaches. Some of  these are simply glorified antenna systems  that utilize a directional “Donor Antenna” on the exterior of  the building to capture signal and then route it through a Bi-Directional Amplifier (BDA); other, more sophisticated systems, use carrier authorized/supplied backhaul connected to a series of fiber remotes. Depending on factors like the size and location of the building and the number of users, one of these approaches is typically preferred.

Cellular Systems Aren’t Mandated by Code

Unlike an Emergency Responder Radio Communication System (ERRCS), these cellular systems are not mandated by code to be installed in any new building in California and most other states. Might this change?

At the risk of alienating the Milton Friedman supporters out there, we believe so. Roughly 80% of 911 calls come from cell phones – a number that continues to rise every year. With 88% of our time indoors, it doesn’t take a math PhD to figure out that 911 calls from inside buildings is the largest category of usage (and will continue to trend upward).

So, if we’re mandating that First Responders radios work in a building, why aren’t we mandating that cellular phones work in a building? The primary way First Responders are dispatched to a building is through a 911 call: no call, no dispatch. Cellular 911 and Public Safety radio are flip sides of the same coin.

Some would argue that the last thing developers or owners need is another government mandate that will cost them money while the revenue goes elsewhere. Of course, this is the same situation with providing electrical, heating, A/C and water into a building. Another argument is that there are alternative wireless technologies to cellular that might mitigate the issue and be less costly to implement (e.g., WiFi and CBRS).

Fire & Building Code Organizations Should Enforce 911 Cellular Support

There’s also the laissez-faire argument that suggests mandates aren’t required because consumers will ultimately choose to live or work in buildings knowing the extent of the 911 coverage. Likewise, most developers of hotels, multi-family residential buildings and commercial buildings know that cellular service is no longer just an amenity in a new building, but a requirement if you expect guests and tenants. But there’s always an exception.

Perhaps its time for the Fire and Building code organizations to look into some level of mandatory support for 911 inside buildings? They certainly should be encouraging (in our view) the coupling of system elements (like coax or fiber) that could support both cellular and ERRCS – providing some technical and economic incentive to install both concurrently.  One big caveat here: mandated support for cellular 911 and ERRCS doesn’t mean a system will always need to be installed. If the relevant wireless signal is sufficient inside the building, a simple test report forwarded to the relevant Authority Having Jurisdiction (AHJ) will obviate the need for a system. But it is an explicit acknowledgment that both Cellular 911 and ERRCS work inside the building (at least at that point in time).

Contact Us

Let us know what you think. If you need assistance in the design, testing and installation of either a cellular DAS or an ERRCS, please reach out to us.