Routine reaction rate comparison studies of highly corrosive gaseous fluorides, such as CIF3and F2, extending to temperatures above 100°C required the development of an improved heated ir gas cell. The cell features cooled window gaskets composed of Teflon, all nickel construction, and a tapered sample space to reduce the internal volume. The internal temperature of the cell can be accurately determined and controlled by the use of parameter design charts to set the control variables. The cell, which has proven to be reliable and easy to operate for the intended service, has also been extended to applications requiring vaporizing air sensitive compounds onto the cooled windows for direct ir observation.