I am often asked about privacy in the home, office, hotel, etc., and how to check for secret listening and video devices. Here are a few things to look for.
Visual Search/ Signal Detectors
This search requires absolute darkness. Lights must be off and blinds closed. Some devices have lights that are illuminated when turned on. A flashlight or camera detector (app or hardware) can assist in locating devices. Due to electromagnetic interference there are phone apps and hardware that can help in this search. Also check mirrors, they can be made to be transparent so a camera can record activity through them. Some people are smart and cover the lights with tape, but not always.
There are so many different cameras and recording devices on the market it’s impossible to name them all. Devices can be hidden in anything and look like anything. A teddy bear, pen, glasses, button, USB drive, cup, bag, anything can have a device planted.
Conduct a complete physical search of the area you suspect might be bugged or wired. This involves a meticulous and deliberate sweep of the room you believe might have a hidden recording device. Be aware of lights and sound when checking the room. Some devices are motion sensitive and make a buzz or clicking sound when they operate. Other devices can be on a timer or on all the time.
Hire a Professional
There are professionals that specialize in this business, above and beyond what a Private Investigator provides. These folks usually charge a flat fee and charge by the square foot (usually $1-$2 per square foot). They often are former Intelligence Agents, and use terms like TSCM, which is Technical Surveillance of Counter Measures. For serious needs, use these guys. It’s expensive, but if you are concerned about corporate espionage or something similar, this is your best bet.