Determination of quartz on membrane filters by X-ray diffraction

An X-ray diffraction method is described for the quantitative determination of quartz in dust samples. The analysis was done directly on a collecting cellulose ester membrane filter of the type used in an air sampler. Quantitation was achieved by the measurement of the quartz line intensities with a digital integrator and by the comparison of these values with those measured from calibration standards prepared on similar filters with water suspensions. The overall precision of the procedure was 8%. When the method was applied to foundry dusts, the accuracy of the quartz analysis was fou,d to be within 10% at the 1- to 10-mg level of total loading. The detection limit for quartz was below 0.1 mg.