Read the signs carefully
Most lists of “signs you’re being bugged” are full of phone line crackle, radio interference and strange noises. Most of those have innocent explanations, and today’s devices rarely leave a noticeable trace. Read signs together, not one at a time.
The strongest indicator in an office is usually not technical but informational: something discussed only in one room, between particular people, ends up in someone else’s hands.
Information signs
- A decision, price or strategy discussed only in a closed meeting is known outside
- A competitor seems unusually well prepared for your bid, tender or product plan
- In a negotiation, the other side behaves as if it knows your internal assessment
- Unannounced information circulates in the press or your sector
First consider the other routes: an email, a document, a slide deck or an attendee talking. Noting which information was discussed in which meeting, with whom, narrows the possibilities. If it was only ever said in one room and is hard to explain any other way, that room becomes the priority.
Physical signs
New or moved objects
An adapter, power strip, clock, pen holder or ornament in the meeting room that nobody remembers bringing deserves attention, as does furniture or equipment that has moved. Keeping a list and photos of critical rooms makes changes easy to spot.
Ceilings, sockets and covers
A ceiling tile slightly out of place, a socket cover with a new or loose screw, a fresh hole or paint mark can indicate tampering. Ordinary maintenance causes the same marks; what matters is whether you know who did the work and when.
Debris
Unexpected dust, plaster or plastic fragments under a desk or ceiling tile can show someone opened and closed a surface.
Gifts and promotional items
Electronic gifts to executives, such as clocks, charging docks and speakers, sit unquestioned for months. If the source is unclear or unexpected, check it before it goes into a critical room.
Electronic signs: be careful
Line crackle, interference on speakers or a flickering TV are often listed. Some once applied to old analogue transmitters. Today they are overwhelmingly caused by a mobile phone near a speaker, old cabling or everyday interference. A device sending audio over the mobile network can make the familiar buzz a phone makes near a speaker, but so can any phone in the room. Treat electronic signs as a prompt to measure, not as evidence.
Access and event signs
- A service, maintenance or cleaning visit you weren’t told about
- Unexplained out-of-hours entry to critical rooms
- The departure, or contentious dismissal, of someone in a sensitive role
- Refurbishment, relocation or a new meeting room fit-out
- A merger, acquisition, tender or legal case that attracts outside interest
None of these proves a device exists, but each creates an opportunity or motive. Combined with an information sign, a sweep makes sense.
When you notice signs
Keep the suspicion out of the suspected space: not in the meeting room, not on its phones, not on corporate email. Tell as few people as possible; a suspicion shared widely may reach whoever placed a device. Contact a specialist from another device and channel, and use a neutral calendar entry. If you think you’ve found a device, don’t touch or move it; photograph it and leave it in place.
When a professional sweep is needed
A concrete leak, physical tampering or one of the access events above all justify an office sweep, which combines RF analysis, NLJD, thermal and optical checks, physical inspection and line analysis. That is how a sign gets assessed by measurement rather than guesswork.