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<p>The <span class="inline-formula"><i>μ</i></span>Dose system is a recently developed analytical instrument applying a combined <span class="inline-formula"><i>α</i></span>- and <span class="inline-formula"><i>β</i></span>-sensitive scintillation technique for determining the radioactivity arising from the decay chains of <span class="inline-formula">²³⁵U</span>, <span class="inline-formula">²³⁸U</span> and <span class="inline-formula">²³²Th</span> as well as from the decay of <span class="inline-formula">⁴⁰K</span>. The device was designed to meet the particular requirements of trapped charge dating methods and allows the assessment of environmental (i.e. low) levels of natural radionuclides. The <span class="inline-formula"><i>μ</i></span>Dose system was developed as a piece of low-cost laboratory equipment, but a systematic test of its performance is still pending. For the first time, we present results from a comprehensive performance test based on an inter-laboratory comparison. We compare the results obtained with <span class="inline-formula"><i>μ</i></span>Dose measurements with those from thick source alpha counting (TSAC), inductively coupled plasma optical emission spectrometry (ICP-OES) and low-level high-resolution gamma spectrometry (HRGS) applied in five participating laboratories. In addition, the reproducibility and accuracy of <span class="inline-formula"><i>μ</i></span>Dose measurements were tested on certified reference materials distributed by the International Atomic Energy Agency (IAEA; RGU-1, RGTh-1 and RGK-1) and on two loess standards (Nussy and Volkegem) frequently used in trapped charge dating studies. We compare <span class="inline-formula"><i>μ</i></span>Dose-based results for a total of 47 sediment samples with results previously obtained for these materials by well-established methods of dose rate determination. The investigated natural samples cover a great variety of environments, including fluvial, aeolian, littoral, colluvial and (geo-)archaeological sites originating from high and low mountain regions as well as from lowlands in tropical areas, drylands and mid-latitude zones of Europe, Africa, Australia, Central Asia and the Americas. Our results suggest the <span class="inline-formula"><i>μ</i></span>Dose system's capability of assessing low-level radionuclide contents with very good accuracy and precision comparable to well-established dosimetry methods. Based on the results of our comparative study and with respect to the practical experiences gained so far, the <span class="inline-formula"><i>μ</i></span>Dose system appears to be a promising tool for trapped charge dating studies.</p>