Abstract: in order to more effectively prevent a gas blowhole phenomenon occurred during the slotting construction process with the high pressure water jet,an optimized design was conducted based on the conventional outburst prevention and collection devic . After the optimization,a rubber pack hole sealing and water injection pressurized working method was applied to the blowout prevention and colection device. The weightof the device was reduced by 50% than the conventional device. Meanwhile a hinge mode open design was applied to the end of thecolection part,thus the operation would be easier and the process would be simpler. Also after the optimization,the impact resistance performances of the bowout prevention and collection device were experienced and test.The optimized device could have good impact resistance performances and the max accumulated impact impulse of the optimized was 1 188 Ns.Site experiment results showed that the borehole volume was reduced about39%~67% than the conventional device. The gas over limit accident could be prevented basically and the optimized device could have better sealing performances and more strong stability.