May 9th, the expert of Sinopec Research Institute of Safety Engineering Yu Yangtian, the director of national petrochemical project safety assessment technology center Doc. Yu Anfeng and the president of Germany Protego Company of China Dr.Zhang Yan visit China National Quality Supervision and Testing Center of Explosion-proof Equipment (For short "CQCEx"). The two sides briefed each other on the basic situation of Sinopec Research Institute of Safety Engineering and CQCEx, and planned the basic thinking of project cooperation. Dr.Zhang Yan gave a special technical report on "Safety precautions for industrial explosion protection system - application of flame arrester"。