NOSE RINGS as someone who's very well-versed in the art of piercing, I get asked this question a lot—usually by those who don't want their precious piercings to be discovered. For instance, if you're going to an airport, sports game, or any other event where a metal detector could be, you might wonder if you're going to end up setting off all the bells and whistles. Before answering the actual question, it'll be helpful to understand how metal detectors work and the reasons they're used for security purposes. A metal detector emits an electro-magnetic field that flows until it comes across something metallic. The metal object disrupts this flow in different ways—depending on its size BODY PIERCING RETAINERS and the type of metal—and is designed to give an audible signal when the field is disturbed. Security metal detectors, like the ones posted up at every airport, are used to look for dangerous objects like knives, guns, explosives, and other weapons that could threaten people's safety on a flight. Adjustments can be made to the metal detector to determine how sensitive it is based on the level of security needed. For example, if necessary, a metal detector might be set to detect just a very small amount BODY PIERCING JEWELRY of metal.