Abstract: A combination RFID tag intended to be associated with a host product, for example by being secured to the outside of a package containing a perishable product, e.g. foodstuffs or vaccines, which RFID tag is provided with a visually readable environmental condition exposure indicator. The visual indicator can sense the exposure of the RFID tag to an environmental condition e.g. temperature, experienced by the host product providing a visual indication, e.g. a color change, readable externally of the RFID tag of the sensed environmental condition. The visual indicator can be chemically active, for example an acetylenic agent, and may be responsive to cumulative temperature excursions over time. The novel RFID tag 11 and tag inspection methods of the invention permit an efficacious harnessing of information about the condition exposure history of a specific inventory item including product identification and related data.

Abstract: A system for recovering a diacetylenic monomer shelf life monitoring compound of reduced particle size and narrow size distribution range which comprises quenching a solution of the monomer by mixing the solution in a lower temperature quenching fluid having a base temperature which is at least about 30° C. below the nominal temperature at which the monomer compound recrystallizes from solution, the mixing being effected in such a manner as to limit the resulting quenching mixture temperature to one which is not higher than a maximum of about 15° C. above the quenching fluid base temperature.