Video surveillance is pervasive and encroaching on virtually every aspect of public and even private life. Municipal governments install and maintain surveillance cameras in public places, such as subways. Corporations hide cameras in the workplace to monitor employees. The Internet is full of websites containing lewd videos of individuals who were filmed surreptitiously by their since-jilted lovers. Micro-cameras can be hidden almost anywhere, and one popular place is within a dummy smoke detector. Here is how to identify them.

Approach the smoke detector from the side if it is wall-mounted, or at an angle if the detector is attached to the ceiling. Video cameras hidden in a smoke detector typically have a field of view no more than 90 to 95 degrees, so if there is a camera inside, a stealth approach is best to avoid being seen and possibly videotaped in the act of investigating the device.

  • Video surveillance is pervasive and encroaching on virtually every aspect of public and even private life.
  • Video cameras hidden in a smoke detector typically have a field of view no more than 90 to 95 degrees, so if there is a camera inside, a stealth approach is best to avoid being seen and possibly videotaped in the act of investigating the device.

Check the test button on the face of the smoke detector, using a stepladder to reach it if it is ceiling-mounted. Circular smoke detectors have a translucent or solid-colour test button to check battery condition and verify that the detector is working. Press the button to test whether the device is a legitimate smoke alarm. If it is a real smoke detector, a series of short beeps will begin.

Place your hand on the sides of the smoke detector; turn the unit counter-clockwise, and release it from the wall or ceiling mount.

Pull the smoke detector housing gently from the wall to inspect the wires inside. Thin electrical wires merely indicate a smoke detector wired into the building's electrical supply. However, larger cables are another story. Any cable about a quarter-inch in diameter that terminates in an RCA-type plug is likely a video cord. Two or more cords indicate video and audio cables, which will be routed into the wall or ceiling to a wireless transmitter box about the size of a pack of cigarettes.

  • Check the test button on the face of the smoke detector, using a stepladder to reach it if it is ceiling-mounted.
  • Two or more cords indicate video and audio cables, which will be routed into the wall or ceiling to a wireless transmitter box about the size of a pack of cigarettes.

Inspect the cables for any markings that might designate their purpose. Any letters such as V or A/V printed on the insulation are a giveaway that the device is a surveillance camera.

Place a small square of duct tape over the translucent button, which actually is a small camera lens, to block the view below the device. However, this will alert the operator that the camera has been discovered, which might prompt the installation of a secret camera somewhere else.

WARNING

Some surveillance systems are available in a bundled package with an actual, working smoke alarm, making detection more difficult. It also illegal to tamper with or disable a functional smoke alarm, so use caution if inspecting a suspicious device on a wall or ceiling.