The problem of copper corrosion that occurs in the presence of strong alkaline developing solutions during photo rework has been overcome by protecting all exposed copper bearing surfaces from attack. For example, in one embodiment, a portable cooking system is provided comprising a cooking plate having a continuous cooking surface, a heating element assembly disposed beneath the cooking surface, a temperature controller for varying the temperature of the cooking surface, and a base that supports the cooking plate on an underlying surface. It may also rank the documents within each cluster according to the frequency of term co-occurrence within the concepts. This allows a first reticle to be removed from the reticle stage with a first hand and a second reticle to be loaded onto the reticle stage with a second hand, and so on, which minimizes exchange time. Upon completion of that known desired quantity of pharmaceutical gas over a plurality of breaths, the system can either terminate, continue, activate and alarm, etc.