There’s a big difference between a building that looks ready and one that actually works the way people expect. One common problem that gets overlooked? Signal coverage.
It’s not just about cell phones. It’s also about whether a firefighter can use their radio in a stairwell. Or whether a police officer can call dispatch from an underground parking level. That’s where DAS and ERCES come into play.
These two systems often work side-by-side, but they’re not the same, and they shouldn’t be treated like they are.
Two Systems, Two Purposes
A DAS, or Distributed Antenna System, handles cellular signal. It makes sure people can make calls, text, or use mobile data inside buildings, especially ones with thick walls or lots of metal.
An ERCES is different. It stands for Emergency Responder Communication Enhancement System. It’s built specifically for public safety radio frequencies, the ones first responders use.
So while both systems improve signal indoors, they’re solving different problems. And most large buildings today need both.
Why You Can’t Use One for Both
Some folks think one system can handle everything. That’s not how it works.
Here’s why:
- Cellular and emergency radios run on different frequencies
- They’re subject to different codes
- Each has different performance requirements
Trying to combine them usually leads to interference, failed inspections, or both. It’s like trying to plug a fire alarm into a Wi-Fi router. They’re built for totally different jobs.
Do They Work Together?
Yes, and often they need to. But “together” doesn’t mean “in one box.” It means planning them alongside each other from the start so they don’t clash and you don’t waste time redoing work.
A proper setup usually looks like this:
- A rooftop antenna for each system, one pulling in public safety radio, one for mobile carriers
- Separate cable runs inside the building
- Amplifiers and power supplies tailored to each signal type
- Antennas installed in areas where coverage is weak, like stairwells, lower levels, long hallways
They stay separate, but they can be installed and managed by the same integrator if done right.
What Happens If You Don’t Plan for Both?
Let’s say you only install DAS. The tenants are happy because phones work fine. But during final inspections, the fire marshal runs a radio test, and fails the building because stairwells don’t have enough coverage.
Now you’re:
- Behind schedule
- Paying extra for rushed installation
- Cutting into walls or ceilings that were already finished
- Dealing with permits and testing all over again
Same story if you only do ERCES and forget about DAS. People start complaining the day they move in that they have to stand by a window to make a call.
Either way, it’s a headache. One that could’ve been avoided with a little coordination up front.
Smart Ways to Combine Planning
If you’re still in the early stages of a build or renovation, here’s what helps:
- Make room for both systems in your low-voltage plans
- Use shared cable trays or conduits if possible (but don’t mix the systems)
- Talk to your AHJ (Authority Having Jurisdiction) about radio testing requirements
- Choose a contractor who understands both systems and has experience installing them in the same building
You don’t need to overcomplicate it. Just make sure both needs are part of the plan, not last-minute extras.
After the Install
Once both systems are in, you’ll need to test and maintain them. ERCES, in particular, usually requires:
- Annual inspections
- Backup power checks
- Documentation for compliance
DAS systems don’t have the same legal requirements, but they still need monitoring. Carriers sometimes update their networks or signals shift, which can affect performance inside the building.
Having both systems documented, tested, and easy to access will save you time later, especially if something needs repair or re-certification.
Final Thoughts
DAS keeps people connected to their world. ERCES keeps first responders connected to each other. Both matter, and neither should be an afterthought.
When they’re planned together, installed with care, and kept separate where it counts, you get a building that’s not only more usable, but safer for everyone inside.
