Access to the back to the back is how the matter
Speaking of the popular point is that when the door must rinse the card, if accompanied by someone else, and out of your card that is the right through the door, playing can not, and vice versa, go out to rinse the card. Anti-submarine back is through the door when the rinse card, an effective solution to personnel to follow the entry
Anti-submarine back regulation: also known as anti-trailing, the function is if the door is not detected, it will limit the door, or go out without detection, it will limit the door.
That is, you have a card after the door to go out after the record can not enter the door, not two consecutive doors.
