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A practical and inexpensive method for desensitization of zirconium powder is proposed by treatment with 1 % hydrofluoric acid for 5 min. The electrostatic energy required to set off the powder increased considerably after this treatment, and the usefulness of the zirconium for primers was not impaired. The effect of the desensitization on visual appearance, appearance under the microscope, particle size, and behavior on burning‐was investigated. The most valid explanation of the desensitization process is that it involves the formation of an adherent layer of zirconium hydride by the reaction of the zirconium and nascent hydrogen generated when the metal is attacked by hydrofluoric acid. Previous investigators not concerned with the problem of desensitization have isolated zirconium hydride films obtained on treating pieces of zirconium metal with dilute hydrofluoric acid. Treatment with nonoxidizing acids produces varying degrees of desensitization, but the use of hydrofluoric acid is preferable. All work on desensitization was performed using zirconium powder intended for use in primers, but the method can also be used for zirconium powder intended for other purposes.