Corrosion of refractory silica brick and air quality issues due to particulate emissions are two important glass manufacturing issues that have been tied to sodium vapor and its transport throughout the melt tank. Knowledge of the relationship between tank operating conditions and tank atmosphere sodium levels are therefore important considerations in correcting corrosion and air quality issues. However, until recently direct quantitative measurements of sodium levels has been limited to extractive sampling methods followed by laboratory analysis. Excimer laser induced fragmentation (ELIF) fluorescence spectroscopy is a technique that permits the measurement of volatilized NaOH in high temperature environments on a timescale of less than one second. The development of this method and the construction of field-portable instrumentation for glass furnace applications are herein disclosed. The method is shown to be effective in full-scale industrial settings. Characteristics of the method are outlined, including equipment configuration, detection sensitivity, and calibration methodology.