Automatic integrated sensing and access control

1. A transit system for sensing exposure to an item of interest, the transit system comprising:

a unique identifier of a media;

an exposure detector that detects exposure of the media to the item of interest, wherein the exposure detector determines whether the media has been exposed to the item of interest based, at least in part, on a detected optical change in a detection material of the media;

a processor coupled to the exposure detector, wherein:

the unique identifier is flagged when the exposure to the item of interest is detected, and

a message is communicated away from the processor to a remote location when the unique identifier is flagged; and

an access control point that:

automatically reads the unique identifier of the media, and

denies access beyond the access control point based, at least in part, on a determination that the unique identifier is flagged.

2. The transit system for sensing exposure to the item of interest as recited in claim 1 , wherein the detected optical change in the detection material includes one or both of a change in color and a change in reflective photoluminescence.

3. The transit system for sensing exposure to the item of interest as recited in claim 1 , wherein data beyond that gathered by the exposure detector's interaction with the media is used in determining if the unique identifier is flagged.

4. The transit system for sensing exposure to the item of interest as recited in claim 1 , further comprising an encoder for storing information on the media.

5. The transit system for sensing exposure to the item of interest as recited in claim 1 , wherein the item of interest comprises a chemical compound, nuclear material, radiological material, biological agent, or explosive.

6. The transit system for sensing exposure to the item of interest as recited in claim 1 , further comprising an image capture device.

7. The transit system for sensing exposure to the item of interest as recited in claim 1 , wherein the media comprises a fare card or ticket.

8. A system for sensing exposure to items of interest for a person associated with an identifier that is machine-readable from access control media, the system comprising:

the identifier of the access control media associated with the person, the identifier being machine readable from the access control media;

an exposure detector that detects whether the access control media has been exposed to one or more items of interest based, at least in part, on a detected optical change in a detection material of the media;

a processor coupled to the exposure detector, wherein:

the identifier is flagged when the exposure to one or more items of interest is detected, an exposure condition being stored by the access control media, and

a message is communicated away from the processor to a remote location when the identifier is flagged; and

an access control point that reads the identifier of the access control media, wherein the identifier is used, at least in part, to determine whether to allow access beyond the access control point.

9. The system for sensing exposure to items of interest for a person associated with an identifier that is machine-readable from access control media as recited in claim 8 , wherein the detected optical change in the detection material includes one or both of a change in color and a change in reflective photoluminescence.

10. The system for sensing exposure to items of interest for a person associated with an identifier that is machine-readable from access control media as recited in claim 8 , wherein the association between the person and the identifier is that the person possesses the access control media.

11. The system for sensing exposure to items of interest for a person associated with an identifier that is machine-readable from access control media as recited in claim 8 , wherein the items of interest comprise at least one of chemical compounds, nuclear materials, radiological material, biological agents, or explosives.

12. The system for sensing exposure to items of interest for a person associated with an identifier that is machine-readable from access control media as recited in claim 8 , further comprising an image capture device.

13. The system for sensing exposure to items of interest for a person associated with an identifier that is machine-readable from access control media as recited in claim 8 , wherein the exposure detector detects exposure to the items of interest from the person's contact to the access control media.

14. The system for sensing exposure to items of interest for a person associated with an identifier that is machine-readable from access control media as recited in claim 8 , wherein the access control media comprises a fare card or ticket.

15. A method for flagging a media used in an access control system based, at least in part, upon exposure to at least one predetermined item of interest, the method comprising:

providing a machine-readable identifier associated with the media;

determining if the media was exposed to the at least one predetermined item of interest based, at least in part, on a detected optical change in a detection material of the media;

flagging the machine-readable identifier when the determining results in a determination that there was exposure to the at least one predetermined item of interest;

notifying a point away from a location where the machine-readable identifier was provided that the machine-readable identifier is flagged;

automatically reading information from the media; and

controlling access of a person based, at least in part, on whether the machine-readable identifier is flagged.

16. A method for flagging a media used in an access control system based, at least in part, upon exposure to at least one predetermined item of interest as recited in claim 15 , wherein the detected optical change in the detection material includes one or both of a change in color and a change in reflective photoluminescence.

17. A method for flagging a media used in an access control system based, at least in part, upon exposure to at least one predetermined item of interest as recited in claim 15 , wherein at least two of the elements are performed by a device configured to do at least one of read, write, or verify information from the media.

18. A method for flagging a media used in an access control system based, at least in part, upon exposure to at least one predetermined item of interest as recited in claim 15 , wherein the media comprises a fare card or ticket.

19. A method for flagging a media used in an access control system based, at least in part, upon exposure to at least one predetermined item of interest as recited in claim 15 , wherein the providing the machine-readable identifier comprises reading a magnetic stripe, RFID, smart card, bar code, and/or optical indicator of the media.

20. A method for flagging a media used in an access control system based, at least in part, upon exposure to at least one predetermined item of interest as recited in claim 15 , wherein the predetermined item of interest comprises at least one of chemical compounds, nuclear materials, radiological material, biological agents, or explosives.

21. A method for flagging a media used in an access control system based, at least in part, upon exposure to at least one predetermined item at least one as recited in claim 15 , wherein the determining includes detection of whether the media has been exposed to the at least one predetermined item from the person's contact with the media.