An access control system for use in a process control system within a process plant, the access control system comprising: a computer readable medium; and a first routine stored on the computer readable medium which, when executed by a processor, determines the geographic position of an authorized user operating a portable communication device with respect to a plurality of control areas (102, 103, 104) of the process plant based on data received from one of the portable communication device or electronic location device carried by the authorized user; a second routine stored on the computer readable medium which, when executed by a processor, limits access of the authorized user to data within the process plant based on the determined geographic position of the portable communication device with respect to the plurality of control areas (102, 103, 104) of the process plant; a third routine stored on the computer readable medium which, when executed by a processor, receives, from the user of the portable communication device, data indicative of the authorization level of the user; and a fourth routine stored on the computer readable medium which, when executed by a processor, stores data indicative of the plurality of control areas (102, 103, 104), characterized by further comprising: a fifth routine stored on the computer readable medium which, when executed by a processor, selectively notifies the portable communication device of an event associated with an element (110, 130, 131, 150) within the process control system depending on the position of the portable communication device with respect to the plurality of control areas (102, 103, 104); and a sixth routine stored on the computer readable medium, which, when executed by a processor, expands a particular control area of the plurality of control areas (102, 103, 104) for the user of the portable communication device in response to an abnormal condition. a computer readable medium; and a first routine stored on the computer readable medium which, when executed by a processor, determines the geographic position of an authorized user operating a portable communication device with respect to a plurality of control areas (102, 103, 104) of the process plant based on data received from one of the portable communication device or electronic location device carried by the authorized user; a second routine stored on the computer readable medium which, when executed by a processor, limits access of the authorized user to data within the process plant based on the determined geographic position of the portable communication device with respect to the plurality of control areas (102, 103, 104) of the process plant; a third routine stored on the computer readable medium which, when executed by a processor, receives, from the user of the portable communication device, data indicative of the authorization level of the user; and a fourth routine stored on the computer readable medium which, when executed by a processor, stores data indicative of the plurality of control areas (102, 103, 104), characterized by further comprising: a fifth routine stored on the computer readable medium which, when executed by a processor, selectively notifies the portable communication device of an event associated with an element (110, 130, 131, 150) within the process control system depending on the position of the portable communication device with respect to the plurality of control areas (102, 103, 104); and a sixth routine stored on the computer readable medium, which, when executed by a processor, expands a particular control area of the plurality of control areas (102, 103, 104) for the user of the portable communication device in response to an abnormal condition. a fifth routine stored on the computer readable medium which, when executed by a processor, selectively notifies the portable communication device of an event associated with an element (110, 130, 131, 150) within the process control system depending on the position of the portable communication device with respect to the plurality of control areas (102, 103, 104); and a sixth routine stored on the computer readable medium, which, when executed by a processor, expands a particular control area of the plurality of control areas (102, 103, 104) for the user of the portable communication device in response to an abnormal condition.