Abstract: According to the requirements in the Code for Design of Oil Depot (GB 50074-2014), a new technique has been developed for discharging oil/gas from the strainer at pump inlet of oil pump control room. It is that a control valve and an observation mirror on the valve are installed at the discharging inlet of strainer on each pump. With the observation mirror, timing for valve shut-down can be controlled properly. In addition, overflowing oil during the discharging process can be recovered without power unit. This technique is characterized by simple structure, good sealing performance and easy operation. It also eliminates the sources of oil/gas in pump controlling room to minimize risks of oil/gas-induced explosion. Therefore, this technique may effectively ensure the health and safety of operators engaged in prolonged operations in an environment with high concentration oil/gas. It can also significantly reduce stains and traces of oil generated by discharging of strainers. In summary, this new technique provides desirable performances in safety, environmental protection and energy conservation with less labor cost.