290B Parker Farm Road, Buxton, ME 04093
(207) 929-9149 (ph), (866) 459-5150 (fax)
Scott Nason - Director of Technology

Thursday, April 21, 2016

Building Access Control

Building Access Control

In the name of building security and safety, MSAD 6 has been working towards hardening and improving the physical security of all school buildings.  Currently the district is focusing on doors and methods of controlling entry into schools.  

Recently the District started by installing two way communications at all main entrances of schools called Aiphones.  This now gives everyone the ability to see and speak to who is requesting entrance to a school without having to place someone physically at the door, where something bad could happen.

Now this year, the District is taking the next step and is installing an Access Control system at every school.  This system will now allow the schools to keep all doors closed and locked, but still allow staff and teachers to exit and enter the school without having to give everyone a physical brass key.  

This system uses what are called Proximity Cards. What are Proximity Cards?  Proximity Cards, or Prox Cards for short, are thin plastic cards that have a small chip embedded inside them.  This chip contains information that allows an Access Control system to know whether the user holding the card has the rights to unlock and enter the building.

Image of a Proximity Card  Image of inside a Proximity Card

The Prox Cards themselves do not contain any personal or valuable information.  The only thing contained within the chip of the card, is a series of numbers that mean nothing to anyone or thing, except for the Access Control system.

Prox Cards are very durable and long lasting, there are no batteries to run down, and the cards are literally molded around the chip and wires so they are waterproof.  The only thing that can damage a Prox Card are microwaves.

Prox Cards work by absorbing the radio waves that scan plates located near doors admit.  These radio waves energize the coil of wires within the card and power up the chip.  This chip then sends back a radio transmission to the scan plate and unlocks the door.

Sadly, microwaves transmit radio waves as well… ALOT of radio waves.  A scan plate will transmit at about 0.5 watts worth of power, a microwave transmits at about 800-1000 watts of power.  This is enough power to literally cook the chip in the Prox Card and will make the card useless.  So please do not wear your badge near a microwave when it is in use.

Prox Cards have some huge gains over standard physical keys, when it comes to building security. One such benefit is the ability to change who can access a building.  

Before with a physical key, if the key was lost, who ever found the key could now enter the building at anytime.  Now with a Prox Card, if the card is lost, once you contact the building administrator or the technology department, the card is instantly deactivated.  So even if someone finds the card, the Access Control system knows the card is coded as “lost” and will not allow entry.

Another benefit is the ability to limit who can enter which building and when they can enter.  One example is a card for one person may give them entrance to building A, but not building B or C. Another person’s card could not give them entrance to building A, but they could enter building B and C.  Yet another card could allow entry to building A, but not building B, and yet they can enter building C only after 9am.  

One card, infinite possibilities.