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Ophthalmic brachytherapy treats eye lesions by stitching plaques containing a radionuclide (e.g. Ru-106) onto the sclera. Compliance with quality assurance standards is crucial, but practical limitations complicate independent source strength measurement in clinical practice. In this article, a new prototype for acceptance testing of Ru-106 plaques is assayed to assess its suitability for a hospital's medical physics department. The system designed for Ru-106 plaque assessment includes a phantom basin fillable with water, a Si-diode for electrons coupled with an electrometer, type-dependent plaque holders and a micrometre gauge. Testing involved the measurement of three plaque types (CCA, CIB, COB) by six medical physics experts and trainees, the assessment of inter and intra-observer variability and the suitability for measurement at the reference point, 2 mm. Measured absorbed dose rates in water at 2 mm from the plaque surface demonstrated compatibility across all testers for the three plaques. Intra and inter-observer variability was minimal (1.0% and 1.3% of the measured value, respectively), confirming system robustness in terms of operator influence. The system proves suitable for Ru-106 plaque acceptance testing ensuring accurate plaque positioning and dose rate verification at 2 mm. These findings confirm its potential as a support for compliance with quality assurance standards. These results are subject to the issue of the corresponding calibration certificate for the Si-diode. • Technical difficulties to verify the dose rate to water for Ru-106 plaques represent an anomalous situation in brachytherapy. • Beta testing of a new prototype for acceptance testing of Ru-106 plaques in ocular brachytherapy is presented. • The system proves suitable for clinical use, ensuring robust operator handling and adequate dose rate verification at 2 mm. • The prototype has potential to address gap in quality assurance, thereby enhancing patient safety and clinical outcome. [ABSTRACT FROM AUTHOR]