How Banner Health Boosted Its Network Reliability

Hospitals are ill-equipped to own and operate their own cell-signal-extending equipment inside their facilities. The right network service provider can get the job done and raise reliability to carrier-grade levels.

Wi-Fi has been an essential element of information technology infrastructure for nearly 20 years, but in the quest for ever-more-reliable IT, healthcare organizations are opting for in-building cellular networks which increase uptime and could possibly save lives.

It wasn't that many years ago that hospitals banned the use of mobile phones inside hospitals, initially out of fear that they would interfere with everything from delicate medical equipment to someone's pacemaker. Many of those fears were overblown, but over time, interference among devices seems to have been lessened by smarter embedded radios, coupled with a diminishing number of reports of interference.

Users flat-out demanded to use their cell phones in hospitals. And just as over time, it has become OK to use mobile phones upon landing and while taxiing to the airport gate, mobile phone restrictions in hospitals gradually evaporated.

The question then turned to how to get stronger cellular signals in those areas of the hospital where reception was poor.

"Hospitals are great big thick dark facilities with areas that have lead-lined walls and steel mesh and all sorts of things that are just the ultimate enemy for a cell phone," says James Plugfelder, senior director of IT, network, and communications at Banner Health.

This can pose problems.

"A good example is an obstetrician who's got a mother that just about to give birth," Plugfelder says. "It  could be now, could be next day, but she's already in the hospital, and he's sitting in a meeting room having a conference, and the mother goes into distress, and they reach out to his cell phone, and it doesn't work, because he's in a basement conference room, and they can't get a hold of him. That's actually a real story, and those are the things that my team is all about—humans and devices communicating with each other."

In order to improve service in basements and heavily shielded areas, hospitals had to think well beyond the capacity of the neighborhood's local cell towers. But gone are the days when some slap-dash, in-building cellular signal-booster could perform this task, in hospitals or in any building, for that matter.

Since the cellular frequencies are spectra licensed by the Federal Communications Commission, such boosters were illegal anyway, unless sanctioned by the carriers who license those frequencies from the federal government.

But hospitals are ill-equipped by themselves to negotiate with cellular carriers, or to own and operate their own cell-signal-extending equipment inside their facilities.

So Banner turned to ExteNet, a company which acts as interface to the carriers. ExteNet also builds, installs, owns, and operates in-building, distributed-antenna cell services, not only for hospitals, but for a variety of venues such as sports, entertainment, and hospitality services.

Seven Nines
By adding ExteNet equipment and services, Banner could aim for a goal that had eluded the health system despite the fact it had 7,000 wireless access points of its own covering 14 million square feet of hospital.

Until that point, Banner's "patient-grade networking" initiative had achieved "five-nines [99.999%] reliability," Plugfelder says. That meant Banner network users could expect no more than five minutes and 15 seconds of unplanned downtime per year. "That is still too much of an impact on patients' lives for us to consider it," he says. "So we actually shoot for a seven-nines [99.99999%] outage, which is 3.15 seconds of downtime per year."

The flexibility of wireless is part of the solution. "When you've got a wired network, you do have a physical machine with a physical cable that plugs into a physical port somewhere, and when that goes down, you've lost your connection," Plugfelder says.

"In the lovely world of wireless, if we lose any particular single component in our network, wireless clients actually adapt pretty nicely, because they can simply roam to another functioning piece of our network. So in some cases, even though it's more complex, we've had some real good luck with patient-grade networking on the wireless side."

But if Banner were to rely simply on unlicensed spectra, something as mundane as a rogue microwave oven could clobber the network. (Microwave ovens, though normally shielded, can act as giant transmitters on the same frequency as Wi-Fi or Bluetooth when those ovens are damaged or malfunctioning.)

In smaller, single-floor clinics of perhaps 200,000 square feet, reamplifying cell signals from a nearby tower can be a fairly straightforward way to enhance cellular service inside. "When you're getting into million-square-foot facilities, not only do you need to make the signal brighter, but you might need more bandwidth than what that cell tower can handle," Plugfelder says.

The ExteNet gear is engineered in a way that handles the load of users inside the building, but doesn't interfere with the carriers' existing outdoor services.

Gradually, Banner is bringing up all four major U.S. cellular carriers on this hardware, starting with Verizon. Each carrier has its own particular set of technical criteria, which is why it isn't as simple as flipping a single switch to bring up all four at once.

I asked Plugfelder how Banner calculates its return on investing in ExteNet's services. "One way we do it is to take a look at it the negative way, and that's to say, what's the cost of downtime in heartbeats? What really drives our team is, what's the cost of this in regards to patient lives?"

Which brings up the hard-to-reach obstetrician story again. And as Plugfelder points out, Banner is also leading the way in efforts such as its eICUs, where an outage in a "five-nines" situation could impact 1 in 166 alerts during a 14-hour window.

"That's significantly more risky than you commuting for 30 years, [and] more risky than you Bungee-jumping or hot air ballooning or SCUBA diving," he says.

Thus the move to "seven nines" and enhancing in-building cellular coverage.

So the next time a vendor tells you that cellular is going away and everything is going to exist on some mythical "medical-grade" unlicensed spectra product or service, tell them about Banner, which has a 10-year agreement with ExteNet, and expects the need for licensed cellular spectra to be there that long.

Of course, Wi-Fi isn't going away. The two wireless approaches will also complement each other, as they have done in the past.