Abstract: Some potential hazards occur in a sealed radioactive source workshop, because of the inadequate consideration in the original design, the improper construction of supporting facilities and insufficient maintenance. The design principles and key factors are studied from the factors such as process layout, radiation protection and monitoring, radioactive liquid collection and utility systems, and a suitable solution is put forward, including optimizing personnel traffic routes and radioactive material transport routes, enhancing the shielding and monitoring of hot cells, and reinforcing the classification and collection of radioactive liquid waste. In addition, the ventilation, decoration, automatic control and fire protection systems are improved. With these measures above, the potential safety hazards are removed, exposure risks are reduced, applicable statutory and regulatory requirements and follow-up production demands are satisfied, to protect the public and the environment properly.