Cell phone, mp3 player in the lab

[silin]

Is it it safe for electronics in physics labs (spectroscopy devices, lasers, AFM, Teraherz microscope) to use:

- cell phone
- radio
- mp3 player

Can they cause any noise in electronics and distort signals from photon counting detectors or influence lasers somehow? I'm asking because our labs have a sign that no cell phones should be allowed there and I think it's more because if you're adjusting a laser and suddenly your phone calls you may rush and reflect the laser beam in somebody's eye.

 

[berkeman]

The sign is not there because of the startle factor of a ringing phone. RF transmitters can cause interference with various kinds of electronic circuits. The amount of interference depends on many factors, including the type of circuitry and the frequency and strength of the interfering signal.

But there are some environments where any interference at all would be a bad thing, like a passenger airplane's flight controls and avionics, especially during takeoff and landing. Or apparently in your physics lab, where sensitive experiments may be going on. You'd be pretty mad if sombody's jabbering on their cell phone caused bad data to be collected on your experiment, wouldn't you?