The data shown here were not gathered under any stringent external environmental control; therefore, given that testing was performed in an air-conditioned laboratory, it is likely that the system was not challenged in the same way as it would be at its intended point of use. The wide external temperature ranges found in LRS could significantly change the ramp time and/or duration at the desired temperature of the heater, possibly significantly, but the characteristics of the EPCM will ensure that the desired temperature is held for some period of time, regardless without calibration to the ambient conditions or closed-loop control. First principles of heat transfer dictate that the effects of ambient on ramp time and/or duration should be greatest when the desired temperature is furthest from ambient. Thus, the problem should be appropriately non-dimensionalized to identify states of similitude. We plan to explore these phenomena and to evaluate their effects once we have improved our understanding of the intrinsic variation in the assay chemistry sufficiently to evaluate those effects. This evaluation will include trials under actual field conditions.