Experiments have been recently performed which attempted to confirm Critical Ionization Velocity (CIV) ionization by deploying chemicals at high velocity in the ionosphere. Specifically, the CRIT-II Rocket performed a barium release in the ionosphere where observations of Ba+ resonant emissions following the release are believed to have resulted from the CIV process. Calculations are presented here which suggest a significant fraction (if not all) of the Ba+ observed likely resulted from charge exchange with the thermosphere ions and not through CIV processes. The results presented here are pertinent to other CIV experiments performed in the ionosphere. It is recommended that laboratory measurements of the charge exchange cross section between O+ and Ba as well as other metal vapors used in CIV experiments be made. ¿ American Geophysical Union 1991