Data on the reaction of zirconium with oxygen, nitrogen, carbon monoxide, carbon dioxide, hydrogen, and water vapor in the micron pressure range are presented. The reaction products are studied by means of electron and X‐ray diffraction analysis. When zirconium metal powder is exposed to carbon monoxide or carbon dioxide in the temperature range of 600° to 800°C, both zirconium dioxide and zirconium carbide are formed. In agreement with the work of de Boer and Fast, it is found that ductile zirconium strip can dissolve as much as 38 atom per cent of oxygen without the formation of a new phase.A new apparatus for the study of gas‐metal reactions at low pressure is described.