A security metal detector is an electronic device that alerts the operator whenever metal objects pass within range of the device. There are many different types of metal detectors, from walk-through models to hand-held wands. Some systems combine more than one type of detector. A metal detector is often found at entrances of official city buildings, coliseums, and airports and anywhere that screening for guns, knives or other weapons is appropriate.
Though most people are likely familiar with the type of metal detector that is permanently installed, these devices are mobile and can also be rented. A walk-through metal detector is the most convenient screening device, as the operator can simply stand by and watch as each person passes through, one at a time. If the system detects metal it will sound an audible alarm or flash a red light. Belt buckles, wallet chains, or in some instances other non-threatening items might set off the alarm. These items can be removed and the person can pass through again to be re-screened. Plastic trays are often provided to hold items that might trigger the alarm.
Walk-through metal detectors can be placed within short distances of each other without interference. If the expense of a walk-through metal detector is unwarranted, a wand is a very economic alternative for a small event. This metal detector is a hand held device that the operator passes closely over the body of the individual being checked, who stands with feet slightly apart, arms outstretched. Wands are battery-operated and depending on the model, can alert with a light or audible beeping alarm.
Sometimes a hand-held metal detector is used in conjunction with a walk-through device, to screen only those that trip the walk-through detector. Though wand metal detectors are more economical to rent, they are harder on the operators who must bend to wave the wand up and down the legs of each person that goes through the screening processes.