Avoiding a Four-Alarm Fire in VoIP Migration

min read

Key Takeaways

  • When planning a VoIP migration, it is important to assess your fire alarm panel situation early as mitigating potential issues can be costly.
  • Fire alarm control panels typically use phone lines and analog dialers to report trouble to monitoring services; converting these systems to digital encounters several challenges.
  • Most old alarm dialers won't function properly over VoIP or analog gateways because converting analog signals to digital interferes with data transmission, which garbles the signals sent to monitoring stations.
  • Several approaches exist to get around this problem, but all entail significant expenditure, so it's critical to choose the best option early on and include it when estimating the VoIP migration's total cost.

Jason Whitaker is vice president for Information Technology at Transylvania University.

By now, virtually all CIOs are familiar with Voice over IP network (VoIP) phone systems and their benefits. Upgrading your old private branch exchange (PBX) system to a new VoIP model can trim your operating budget's bottom line by greatly reducing power usage and letting you move away from costly dedicated primary rate interface (PRI) phone circuits to network-based session initiation protocol (SIP) trunks. VoIP also gives you a wealth of new telephone features.

Although every institution has plenty of old desk phones to switch out, they probably also have some analog lines that are easier to leave in place. Transylvania University has the occasional analog phone in a classroom or hallway, along with some apartment-door sensors that dial a special monitoring device in our public safety office. In migrating to VoIP, we saw no reason to run network cabling to these spots or pay for a fancy new VoIP phone that would rarely be used, especially when analog gateway devices exist to bridge such analog lines to work with VoIP systems.

However, as you weigh considerations like these for your own VoIP migration, be aware that there is one old analog device that can burn you: fire alarm dialers.

Feel the Burn

Wherever you have a fire alarm control panel in a building, you likely have phone lines running to it. The panel has an analog dialer that dials a monitoring service to report trouble; that service might be an in-house monitoring station or a third party that you pay for monitoring services.

Either way, most old alarm panel dialers will not function correctly over a VoIP system or analog gateway. The reason is that, when they are converted to digital and compressed, analog signals are optimized for voice — not data — so a fire alarm panel is unable to send correct signals to a monitoring station. (Fax lines face a similar problem for the same reason.)

Several approaches exist to get around this problem, but none of them is cheap. It's thus important to factor in the best option for your needs when figuring your VoIP migration's total cost.

Option 1: Run Dedicated POTS Lines

One solution is to run a dedicated Plain Old Telephone Service (POTS) line to each fire alarm panel. However, this solution might require you to pay monthly for a dedicated phone line to each alarm panel location, which can get expensive quickly.

Worse, if you consult the National Fire Alarm and Signaling Code NFPA 72-138, section states that dialers should have "two separate means of transmission," meaning a primary and backup method of communication, which translates to two POTS lines for each panel. If you have this type of setup already, then you are good to go.

Some institutions, however, have their own PBX systems and hook up their panels as internal extensions, which also violates NFPA code: "The primary means of transmission shall be a telephone line (number) connected to the public switched network." In this situation, you must make a change because the panels are connected to your old phone system.

Option 2: Network Your Panels

Another option is to network all of your alarm panels together, then run POTS lines to one panel that dials the alarms for the whole system. Fire security companies love this solution because they get to sell you a lot of upgrades for your fire alarm panels so they can connect together over a network. One perk with this option is that most fire alarm systems now have software that can monitor and report the status of all networked panels.

If you have older fire alarm panels, you might have to completely replace them to be compatible with a network option. If you are fortunate enough to have newer alarm panels that either were networked from the start or can easily be upgraded for network connectivity, this is your best option.

Option 3: Install Network Adapters at Each Panel

figure 1

Figure 1. Fire alarm panel (top) with network
adapter box (bottom)

You can install special network adapters at each panel that convert the dialer signals to transmit over the network to your monitoring service. This option avoids the cost of POTS lines by connecting each panel to the network; it also avoids the drawbacks of having to replace older panels or upgrade them for network connectivity. Figure 1 shows a fire alarm panel with a new box below it containing the network adapter. Note the phone line going from the fire panel into the adapter, then a network cable coming out of the adapter.

To satisfy NFPA 72's requirement for a primary and backup transmission method, you can install two network adapters at each panel to handle the primary and backup dialer connections. However, to truly provide two different communication paths, the two adapters must connect to two different networks. If you already have redundant network paths in your infrastructure, this option might be attractive.

Case Study

At Transylvania University, we have nearly 30 buildings with fire alarm panels. That number alone caused us to shy away from Option 1 due to the cost of paying for two POTS lines at each location. Also, a fair number of our panels are old and would have had to be replaced or upgraded to support network connections, making Option 2 cost prohibitive as well. Option 3 thus became the clear choice for us.

We worked with our fire security vendor to install and configure a network adapter for each alarm panel. Our vendor also provides monitoring services, so it changed our monitoring accounts so they could receive alarm panel data over the Internet instead of through a phone line.

It turns out that the network adapters perform a connectivity check with the monitoring service every few minutes, whereas some dialers dialed in to check the line only every few hours. Even with only one network adapter, the monitoring service quickly notices if a panel does not check in.

So, we consulted with our local fire marshal's office to review and sign off on a design using only a single network adapter at each panel. Because the monitoring service discovers and alerts us within minutes if a panel has not communicated over the Internet, this design was deemed an acceptable solution. This let us shave the cost of our VoIP migration a bit further by reducing the number of network adapters needed for our panels.

To be sure, the National Fire Alarm and Signaling Code is like many other standards documents: it needs to be updated to better reflect the times. Anyone installing a new phone system today is surely going to choose VoIP, so the codes and standards for security and monitoring need to accurately reflect today's best connectivity options.

One wrinkle with Option 3 is that, depending on how many brands and models of dialers you have, your fire security vendor might have to invest considerable time and effort into configuring a network adapter for each one. In our case, we had several different dialer models simply because they changed over time as new buildings were constructed or panels were replaced. To its credit, our vendor spent a few weeks working out the settings for all of our particular dialers and got us converted successfully without too much delay to our overall migration.

Lessons Learned

When planning your VoIP migration, engage your fire security system vendor as early as possible. Dealing with alarm panels will likely add cost and time to your project, so it is wise to have time to weigh your options and the cost implications.

Our fire security vendor's engineers told us that Option 3 is a fairly new approach to converting alarm panels. When we first talked to them about possibilities, they suggested Option 2 because it was their preferred solution. However, the sheer cost for us to replace so many old panels would have delayed or derailed our VoIP migration. Our vendor then did some research and proposed Option 3. Again, discussing options early in your VoIP planning is critical because your fire security vendor might need time to evaluate your situation.

Any change in how your alarm panels function requires training for your local personnel responsible for maintaining panels and responding to alerts. In our case, the monitoring service contacts our public safety department when a panel has a problem. So, we brought those stakeholders together to explain the changes and train them on some of the differences. For example, when an alert says that a panel has not checked in, it might indicate a network or adapter problem that IT needs to investigate.

At many institutions, fire alarms are the responsibility of the facilities management team, not IT, so the two teams might need to collaborate on engaging your fire security vendor and investigating your fire alarm panels. Also, be sure to involve your facilities personnel in any training on the panels and adapters so that they know how to troubleshoot and diagnose problems.


Assessing your fire alarm panel situation is an essential part of planning for a VoIP migration. Mitigating potential panel issues can require both time and money, so the sooner you know your options, the better. Even if you already have a VoIP phone system, it might be worth examining how your alarm panels were actually converted. If you are paying for phone lines at your panels or considering a panel upgrade, other options are available that might save you some money.