Jay. How low in pressure do you need to go? I was also not clear from your question if you are concerned with zero changes as the temperature is changed or if you are concerned about permanent changes once you go to a temperature extreme and return to normal. Many sensor packages have built in compensation for temperature changes. There are two types. One type is analog correction and the other is digital. The idea is to first characterize the zero changes (and span for that matter) at the needed temperatures. From this data, correcting algorithms or analog circuitry can reconstitute the correct readings. To guard against permanent changes, the type of silicon die, constraint and mounting arrangement are key controlling factors. Another requirement is keeping the temperature swings within the specified temperature band of operation. By combining accurate compensation and proper mounting, one can even take a 1 psig sensor below that level and still get a relatively stable sensor. If you need to go extremely lower than 1 psig, then some type of periodic calibration may be required. Checkout www.sensorsmag.com for a listing of sensor companies. On the left tab, under Problem Solvers, Click Buyers Guide. Ametek makes sensors with standard ranges as low as 1 psi. Rich Rosenblum Principal Electrical Engineer Ametek USG, PMT Products 215-354-1826 rich.rosenblum@ametek.com