E911 & The Z-Axis: Indoor Location Technology To the Rescue

For those who don’t work in rescue services, it’s not always clear what to do in an emergency. But there’s one action that’s ingrained in all of us: call 911.

The first American 911 call was made in 1968, from a mayor’s office in Haleyville, Alabama. In Canada, Winnipeg was the first city to adopt a central emergency number in 1959. Today, the vast majority of North Americans have access to rescue services through 911.

Despite ongoing improvements to the service in both countries, it still has its limitations. The proliferation of mobile phones has created new challenges, including difficulties determining precisely where calls are coming from.

Recently, government requirements have forced wireless carriers to provide location information for 911 calls. Using GPS and triangulation technology, Enhanced 911 (E911) has been successful in pinpointing locations. But only outdoors.

When calls are made from malls, museums, warehouses, office towers and other indoor spaces, accurately pinpointing someone’s location is next to impossible. Fortunately, recent advances in indoor location technology are set to solve the problem. Correctly harnessed, they’ll transform the face of e911.

Location and emergency services

When people use landlines to communicate, it is relatively easy to locate where calls originate. Phone numbers are connected to fixed addresses, which allows dispatchers to send emergency services to the right places.

But today more than 75% of 911 calls are made by cell phones. The immediate access to making a 911 call has had undeniable safety benefits, but mobility has created new challenges. Pinpointing call locations has been one of the most significant.

The American Federal Communications Commission (FCC) has been working to resolve these issues. In 1996, the FCC imposed its first set of E911 requirements on wireless carriers. This early phase of E911 stipulated that for each call, carriers had to provide the caller’s telephone number and the location of the antenna receiving it to a local Public Safety Answering Point (PSAP).

These requirements have now expanded and carriers must provide more accurate locations (generally within 50 to 300 meters).  

The Canadian Radio-television and Telecommunications Commission (CTRC) has enacted similar rules. In 2009, the CTRC gave providers one year to implement changes that would make it possible to track the locations of 911 calls within a 10 to 300m radius.

To meet these requirements, wireless carriers use GPS and triangulation technology to access this information.And while these solutions have worked well outdoors, there’s still a huge piece of the puzzle that’s missing.

Why 911 still doesn’t work everywhere

A man collapses on the ground in a mall. People rush to his side, and several cellphone calls are made to 911.

One caller gets cut off, and another can barely be heard through the commotion. A third can provide two landmarks—the names of nearby stores. Unfortunately, responders on the scene don’t have an intimate knowledge of the building’s layout, so this information doesn’t help them.

The mall is approximately 1,700,000 sq ft in size. As a result, responders waste precious minutes searching for the man after they arrive.

The dispatcher wanted to provide the precise location of those who called 911—but couldn’t.

E911 has greatly improved the responsiveness of emergency services. Unfortunately, it’s not always reliable.

The GPS that provides location so well when callers are on out the street doesn’t penetrate buildings meaning calls to 911 indoors often do not transmit the caller’s location effectively or not at all. WiFi access points can be used to provide indoor positioning—but without supporting technology, the location information provided is often inaccurate.

Buildings present another problem for first responders -- multiple floors. When the caller’s location information is obtained, it’s only the horizontal location that is known and not the floor of the caller (often referred to as z-axis).

Governments have once again turned to wireless carriers to find a solution. Unfortunately, some American critics—such as the International Association of Fire Chiefs (IAFC)—say current expectations don’t go far enough.

According to the IAFC, the FCC has accepted a roadmap agreement that could lead to imprecise location information.

The agreement was entered into by four nationwide wireless carriers along with the National Emergency Number association (NENA) and the Association of Public Safety Communications Officials International (APCO).

In a recent article, fire chiefs Gary McCarraher and Jim Goldstein take issue with its use of the term “dispatchable location” (DL) to describe a caller’s WiFi access point.

Their rationale is that WiFi often provides imprecise location information, the access point nearest to a caller isn’t necessarily her location. McCarraher and Goldstein raise concerns about paramedics kicking down the wrong doors in apartment buildings—or entering adjacent buildings.

Solving the problem indoors

Knowing where smartphone users are located indoors can provide benefits in many sectors—including healthcare, warehousing and logistics, and (of course) retail.

This information has the potential to improve operational efficiency, drive revenue, and make day-to-day tasks more convenient for end users. By improving the accuracy of E911 indoors, it can also to save lives.

Technology developers have created various solutions—from beacons to geomagnetic positioning. While these technologies are promising, they also come with drawbacks, such as poor accuracy and challenging maintenance.

Luckily, recent advancements have led to a breakthrough. InnerSpace’s mapping and positioning platform uses the right combination of several technologies—including LiDAR, Bluetooth, and WiFi, among others—to provide highly accurate indoor locations and positioning.

As soon as the InnerSpace sensors are placed in an indoor space, they create 2D and 3D maps. This map is updated continuously to capture changes within the space.  Positioning technologies work in conjunction with these maps to provide the precise locations of the people and things inside. More importantly for e911 requirements, is the ability for the InnerSpace platform to accurately pinpoint location based on the Z-axis requirements.

 The Z-Axis Location

The illusive z-axis has been difficult to obtain because there hasn’t been a way to connect the caller’s phone number to their position within a building. Until now:

The InnerSpace platform created 2D and 3D maps in real-time and as people move from one floor to another, their movement is tracked across each floor map using the WiFi and Bluetooth features on their phones.

The dispatcher knows the phone number of the caller. The telecom provider converts the phone number to the device’s unique 15-digit IMEI number. This number can then be used to identify the individual’s position in InnerSpace.

This approach protects the individuals privacy - only giving full access to that person’s location to the emergency response team which can then use the InnerSpace wayfinding app to quickly locate the person in need once on site.

For governments—and the service providers who must meet evolving requirements—this technology is enormously promising. Mandating its implementation in public buildings could mean solving the problems associated with E911 access indoors.

Once the mandate is passed down from governing bodies around the globe, there will be a transition period as buildings become enabled with enhanced indoor 911 access. This presents an opportunity for building landlords to differentiate their properties by implementing InnerSpace and marketing the enhanced safety benefits to prospective tenants.

Let’s return to the emergency at the mall. Imagine the property management company that owns the building had implemented InnerSpace in the building. The owners implemented the sensors to provide turn-by-turn navigation for consumers on their mobile phones—much like Google Maps does outdoors.

If wireless carriers used the information collected by the sensors, they could have provided the local PSAP with access to the precise location of the person, saving precious time.

The bottom line

Since its inception, E911 has undergone continuous improvements. The result has been increasingly accurate information regarding the locations of callers.

For far too long, indoor location has been missing piece of the E911 puzzle. Luckily, we’ve finally found a solution. By harnessing the capabilities of real-time maps that work with advanced positioning, wireless carriers can dramatically improve response times to emergencies that occur indoors.