A system for monitoring a compressed gas stream , the system comprising: a monitoring device comprising a plurality of sensors , each configured to sense a value of a condition of the compressed gas stream , and a first wireless communication device configured to wirelessly transmit data relating to the sensed condition values; and a receiving device comprising a second wireless communication device configured to receive the data transmitted by the first wireless communication device , characterized in that the system further comprises: a first user interface module configured to provide a first user command and a second user command; a first memory storage device configured to store a first range for each of the sensed conditions, and configured to modify one of the first ranges in response to the first user command; a first display device configured to receive and display one or more sensed condition values, and to change the displayed condition value in response to the second user command; a first criteria evaluation module configured to receive the sensed condition values, to compare each of the sensed condition values to the first range of the condition, and to provide a first warning signal in response to the comparing; and a first warning indicator configured to provide a visual or audible warning in response to the first warning signal; wherein each of the first user interface module , the first memory storage device , the first criteria evaluation module , and the first display device is included in one of the monitoring device and the receiving device . a monitoring device comprising a plurality of sensors , each configured to sense a value of a condition of the compressed gas stream , and a first wireless communication device configured to wirelessly transmit data relating to the sensed condition values; and a receiving device comprising a second wireless communication device configured to receive the data transmitted by the first wireless communication device , characterized in that the system further comprises: a first user interface module configured to provide a first user command and a second user command; a first memory storage device configured to store a first range for each of the sensed conditions, and configured to modify one of the first ranges in response to the first user command; a first display device configured to receive and display one or more sensed condition values, and to change the displayed condition value in response to the second user command; a first criteria evaluation module configured to receive the sensed condition values, to compare each of the sensed condition values to the first range of the condition, and to provide a first warning signal in response to the comparing; and a first warning indicator configured to provide a visual or audible warning in response to the first warning signal; a first user interface module configured to provide a first user command and a second user command; a first memory storage device configured to store a first range for each of the sensed conditions, and configured to modify one of the first ranges in response to the first user command; a first display device configured to receive and display one or more sensed condition values, and to change the displayed condition value in response to the second user command; a first criteria evaluation module configured to receive the sensed condition values, to compare each of the sensed condition values to the first range of the condition, and to provide a first warning signal in response to the comparing; and a first warning indicator configured to provide a visual or audible warning in response to the first warning signal; wherein each of the first user interface module , the first memory storage device , the first criteria evaluation module , and the first display device is included in one of the monitoring device and the receiving device . <EOS>