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PURPOSE This work presents the clinical validation of RayStation's electron Monte Carlo Code by use of diodes and plane parallel radiation detectors in homogenous and heterogeneous tissues. Results are evaluated against international accepted criteria. METHODS The Monte Carlo based electron beam dose calculation code was validated using diodes, air filled and liquid filled parallel radiation detectors on a Elekta Linac with beam energies of 4,6,8,10 and 12 MeV. Treatment setups with varying SSD's, different applicators, various cut-outs and oblique beam incidences were addressed, together with dose prediction behind lung, air and bone equivalent inserts. According to NCS (Netherlands Commission of Radiation Dosimetry) report 15 for non-standard treatment setups a dose agreement of 3 % in the δ1 region (high dose region around Zref ), a distance to agreement of 3 mm or a dose agreement of 10 % in the δ2 region (regions with high dose gradients) and 4 % in the δ4 region (photon tail/low dose region) were applied. During validation, clinical routine settings of 2×2×2 mm3 dose voxels and a statistically dose uncertainty of 0.6% (250 000 histories/cm2 ) were used. RESULTS RayStation's electron Monte Carlo code dose prediction was able to achieve the tolerances of NCS report 15. Output predictions as function of the SDD improve with energy and applicator size. Cut-out data revealed no field size neither energy dependence on the accuracy of the dose prediction. Excellent agreement for the oblique incidence data was achieved and maximum one voxel difference was obtained for the distance to agreement behind heterogeneous inserts. CONCLUSIONS The accuracy of RayStation's Monte Carlo based electron beam dose prediction for Elekta accelerators is confirmed for clinical treatment planning that is not only performed within an acceptable timeframe in terms of number of histories but also addresses for homogenous and heterogeneous media. This article is protected by copyright. All rights reserved.