In the process of using security inspection doors, many users will encounter false alarms from security doors because male compatriots generally use belts, females wear steel ring bras, and various small metal objects such as keys. Because the security gate sends out an alarm, the security personnel need to check whether the person passing through has contraband, thereby increasing a lot of work. So, after installing the security door, how can he eliminate small metals without sounding an alarm?

　　When examining metal objects carried by a person, we do not want to detect small metal objects, such as rings and keys, but rather detect larger metal objects. At this time, we can adjust according to the following methods:

 1. select a small metal as a sample, it is the boundary of the object we do not want to detect, such as a bunch of keys.


 2. the sensitivity should be appropriately reduced and the sample should be allowed to pass through the detection gate again. If there is still an alarm sound, the sensitivity should be reduced again until there is no alarm sound when the sample passes.

 3. Improve the sensitivity, let the metal sample pass through the security gate and issue an alarm.
Remember, if you want to reduce the sensitivity of a certain area, you only need to adjust the corresponding position. If you want to reduce the sensitivity of the entire X-ray security door, you must adjust the seventh position. (That is, the adjustment of the overall sensitivity) After the above adjustment, the metal smaller than the sample will not sound an alarm, and the metal larger than the sample can be accurately detected.
When the examinee sounds an alarm through the x-ray security door, indicating that a metal object is hidden on his body, a certain part of the metal object on his body can be roughly determined according to the position of the position alarm light. If you want to determine the exact location of a metal object and find it, you can additionally use a handheld metal detector to detect the alarm object.