ASTRID/TETRA indoor coverage: why every building owner and operator needs this on their radar
Roel De Frene
Picture this: it's opening night of your new event venue, hotel or shopping complex. The hall is packed, the atmosphere is great — and then something happens. A visitor collapses, or smoke develops in a technical room. The fire brigade arrives within minutes, but as soon as they step into the building, their radio goes silent. No connection with dispatch. No coordination between teams. Precious minutes are lost.
This scenario is not fiction. It is exactly why the ASTRID network exists — and why indoor coverage is now a legal and moral responsibility of the building owner and operator.
What is ASTRID and why does it exist?
ASTRID is the national TETRA radio communication network for the Belgian emergency and security services: police, fire brigade, emergency medical services (MUG/100), Civil Protection and justice. It was founded after the realisation that regular GSM networks become overloaded or fail during large-scale incidents (think of Ghislenghien, the 22/3 terror attacks, major fires) — precisely when emergency services need them most.
TETRA (Terrestrial Trunked Radio) is a closed, robust, encrypted digital radio system with group calls, priority and direct communication between teams. One network, all disciplines, one language.
The problem? Radio signals don't just find their way into every building. Concrete, steel, underground spaces, thick insulation, low-emissivity glass — modern construction is a Faraday cage. And that is exactly where emergency services need to be able to operate.
The legal reality: it's no longer a 'nice to have'
Many building owners and operators think ASTRID coverage is something "the operator will sort out". That is no longer true.
Since the law of 15 July 2018 containing various Home Affairs provisions (which amended the original ASTRID law), the obligation of result for indoor radio coverage lies explicitly with the owner of new, large construction and infrastructure works. Previously this was "the building owner/developer", but that concept created uncertainty in case of quick sales after completion. The legislator has closed those loopholes.
In concrete terms, this means:
The building permit can (and often will) contain an ASTRID clause, imposed by the FPS Home Affairs (IBZ) or the local ASTRID safety commission.
The fire brigade performs a coverage test at completion and during periodic inspections. No coverage = no favourable advice = no operating permit, or a conditional approval.
An authorisation from ASTRID to put an installation into service does NOT guarantee the presence of sufficient coverage. That is and remains the responsibility of the owner/developer (see ASTRID's own explicit communication).
The two risks operators underestimate
1. Liability in case of an incident
If IBZ or the fire brigade stated in your permit file that indoor coverage must be measured and guaranteed, and you ignore that — or you let the installation deteriorate after commissioning — you risk being held jointly liable when an incident occurs in which emergency services could not do their job due to communication problems.
In a country with criminal liability for legal entities, where investigating judges invariably comb through the permit history after a tragedy, this is not a theoretical risk. It is exactly the type of detail that weighs heavily in a court file.
2. The permit-related risk
Forget the "major disaster" for a moment. The more everyday scenario is this: a neighbour, competitor or dissatisfied customer files a complaint. The permit is reviewed. It turns out the ASTRID condition was never fulfilled or never re-measured after a renovation? Then your operating permit is at risk — with, in the worst case, a closure order until the shortcoming is remedied.
The cost of a closure of even a single weekend in hospitality, retail or the events sector far exceeds the investment in a proper ASTRID DAS system (Distributed Antenna System).
Who does this apply to in practice?
The obligation mainly applies to new, large construction and infrastructure works, but practice shows that local authorities and emergency zones are setting the bar ever wider. Think of:
Hotels and large hospitality venues
Event halls, concert venues, sports stadiums
Shopping centres and large retail complexes
Underground car parks and tunnels
Hospitals, care homes, schools
Office buildings with high occupancy
Industrial sites with SEVESO classification
Data centres
(from 2500 m² of built surface, or from 150 people in publicly accessible spaces)
In doubt? Have it measured. A professional ASTRID coverage measurement (radio survey) by a recognised integrator costs a fraction of a lawsuit or a forced closure.
What should you do in practice as an owner/operator?
Check your permit file for ASTRID or indoor coverage clauses. Not sure? Ask your architect or the competent authority.
Have a coverage measurement performed before commissioning and after every significant renovation or extension.
Invest in a DAS solution where needed (bidirectional amplifiers, distributed antennas), carried out by an ASTRID-recognised installer.
Document everything: measurement reports, certificates, maintenance contracts. That is your file if something ever goes wrong.
Plan periodic maintenance. A DAS that was compliant in 2018 is not necessarily compliant today — renovations, new wall finishes or even changes to neighbouring buildings can affect coverage.
Conclusion
ASTRID/TETRA indoor coverage is not an administrative formality. It is an obligation of result with your name on it, a permit condition that can make or break your operation, and — above all — a piece of infrastructure that saves lives in an emergency, including those of your own customers and staff.
The question is not whether you need to sort it out. The question is whether you do it before the fire brigade is at your door, or after.
Questions about ASTRID coverage in your project or building? Send us a message — a measurement brings certainty and spares you a file you would rather never have opened.
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