Abstract: Biomarkers, such as chromosome aberration and micronuclei assays, prove to be reliable for facilitating clinical diagnosis in radiation accidents. In a radiation accident in India, chromosomal aberration, γ-H2AX, as well as other blood markers, were detected in accidentally exposed victims. This multi-parametric approach aided in confirming that individuals had been exposed by ionizing radiation. However, doses were impossible to estimate because of a 30-day delay in accident awareness. Exposure dose for victims was estimated using a dose-response curve previously established. Dose estimation, blood cell depletion kinetics, and no appearance of prodromal symptoms suggested that doses of exposure were low. Hematologic investigation, sampling time, and chromosome aberration scoring were all proposed according to data from the victims exposed to ⁶⁰Co. Finally, knowledge regarding chromosome aberration analysis and the importance of international co-operation and assistance should be shared from this accident.