Office bug sweep: protect your company from illegal eavesdropping

What an office bug sweep is

An environmental bug sweep is a structured, technical search for electronic eavesdropping devices in a defined area. The goal is to detect, neutralize, and document any unauthorized equipment—restoring secure, private communications.

• Live audio transmitters (real-time bugs)
• Digital recorders (local memory)
• Hidden cameras integrated in everyday objects
• GSM, Wi-Fi, Bluetooth bugs remotely controlled
• Keyloggers and LAN devices used for data interception

Why companies get spied on

• Unfair competition: stealing clients, price lists, strategy.
• Internal conflicts: former staff or partners trying to cause harm.
• Fraud and blackmail: recordings used to pressure or extort.
• Curiosity or personal revenge.

One confidential conversation overheard by a third party can compromise years of investment.

When to request a sweep

• After sensitive meetings or contract signings
• If you notice strange call noises or unusual network slowdowns
• After unplanned maintenance or suspicious visits
• When leaks of confidential documents occur
• During staffing changes (onboarding/offboarding)
• Before board meetings and high-stakes negotiations
• As prevention, every 6–12 months

Prevention is cheaper than the damage caused by an information breach.

Where bugs hide

That’s why you need specialized equipment and experienced TSCM operators.

How a professional sweep works

1) Pre-assessment

Collect floor plans, room count, network/telephony layout; risk profiling by activity, roles, and information value.

2) Physical inspection

Visual and instrumented checks on furniture, fixtures, and devices with optical scopes, RF scanners, NLJD, and thermal cameras.

3) Radio-frequency analysis

Spectrum analysis and wideband detectors (typically 1 MHz–6 GHz) for GSM/LTE, Wi-Fi, Bluetooth, DECT, VHF/UHF signals.

4) Network and IT checks

Inspection of PCs, VoIP phones, routers, printers; live traffic analysis to spot anomalous outbound connections.

5) Telephony analysis

Testing analog/digital lines, searching for taps and passive mics, PBX verification.

6) Final report and remediation

Formal report with photos and findings; removal and evidence handling per legal procedures; prioritized hardening plan.

Professional-grade tools

• Portable RF detectors and spectrum analyzers
• NLJD (non-linear junction detectors) to find circuits even when powered off
• IR thermal cameras to spot active microprocessors
• GSM/Wi-Fi/Bluetooth detectors (including encrypted traffic)
• LAN toolkits and forensics (e.g., mobile forensics suites) for connected devices

The key is signal interpretation: expertise reduces false positives and speeds up localization.

Typical duration and costs

• Single office: 1–2 hours
• 5–10 rooms: 3–6 hours
• Complex sites: up to 1 working day

Typical range €500–€2,000 depending on area, risk, and tools involved.

Preventive sweeps: an ongoing strategy

• Scheduled sweeps (every 6–12 months)
• Periodic checks on phones, LAN, and Wi-Fi
• Staff awareness on best practices (no unattended devices)
• Secure/controlled meeting rooms for sensitive sessions

What NOT to do if you suspect a bug

• Don’t dismantle suspicious items (risk of evidence loss or self-destruct triggers)
• Don’t discuss it over potentially compromised corporate channels
• Don’t improvise with hobby-grade tools
• Call qualified technicians immediately

Choosing a reliable provider

1. Proven experience in security/intelligence
2. Certified, up-to-date equipment (non-consumer)
3. Total confidentiality and clear legal procedures
4. Signed, written technical report
5. Fast, discreet interventions

Endoacustica Europe has been active for over twenty years in surveillance and counter-surveillance, with high standards and full risk coverage for eavesdropping threats.

Wrap-up

Defending corporate privacy is sound professional practice. Today, bug sweeps are a core element of cyber-intelligence and business protection: they safeguard information, reputation, and operational continuity. Trusting professionals means working safely.

Frequently asked questions