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Given that more than half of the radiation affecting humans is provided by radon and its progenies, surveying them has received a significant level of attention. Solid-state nuclear track detectors are most suited to carry out such surveys, e.g., CR-39-based detectors. Ordinarily, track detectors employ optical microscopes; however, in this study, a new scanner-based calibration and validation system is introduced. After exposure, the detectors were etched in a 6.25 M NaOH solution at 90 °C for 4.5 h; the diameters of the tracks developed in this way were typically 40–60 microns. Tracks were assessed using a Canon Canoscan 9000F scanner with a resolution of 4800 dpi, and Image Analyser software developed by ourselves. For the system calibration, known diameter tracks were prepared using an ArF excimer laser (λ = 193 nm), such that both the shape coefficient and the size of the tracks could be changed within the range of 10–100 μm. The operation of the scanner and the evaluation-shape recognition software were examined using repeatability and reproducibility tests. The system was capable of evaluating 100 detectors in an hour. The repeatability and reproducibility value of the system was excellent, with evaluation of the same detector on several occasions at different times producing a spread of 2%. The maximum spread for scanning in different positions was 3%.