Event badges are nearly always printed with information that staff will scan at access control points to determine whether the person carrying the badge is permitted to enter through a doorway or gate.  That is why event badges tend to be large-format, often 3 or 4 times larger than the traditional ID card, so that staff can quickly and easily read the rights of a person.  When a large number of people are lined up to go through a choke-point, it is essential that staff can keep them moving which filtering out those who are not allowed to enter. As a result, security guards and other staff members at every event, whether it is a sports event, a concert, or a business conference, are trained to recognize the signs on the badge to determine whether or not to allow an attendee to pass through. 

At many events, badges are printed with barcodes or QR codes which can be automatically scanned with a mobile hand-scanner to verify authenticity.  Use of these auto-ID technologies further increases the security at the venue, to make sure that a badge or ticket has not been tampered with. 

A final, even more secure technology which is used in the Event Badging arena to enhance security is RFID.  In this instance, and RFID (Radio Frequency Identification) chip is embedded in the badge itself.  This is a passive transmitter which sends out a unique number to any appropriate reader in close range (generally not more than a few feet.)  The readers are linked to a turnstile or similar gate mechanism, which are only opened if the correct signal is received from the facility’s systems.  The unique number is then used by the facility to validate whether to authorize the opening of the door or gate to allow the person to pass. 

Security is always a major consideration at any event, to prevent unauthorized people from accessing areas which may contain very expensive equipment, or rooms where public figures may be preparing for their performance.  And in many cases, inappropriate access can be an important safety risk or health liability, if for example unauthorized people enter areas under construction.