Brick silo was tested with bidirectional spraying application of inert dust into the grain bulk. Dust sampling method was used to determine the distribution of inert dust. The direct effect of inert dust aerosol on pests was checked by embedded insect cages. The pests control effect in the silo was evaluated by integrated pest monitoring method. The results showed that the inert dust distributed into the grain bulk by bidirectional application. The silo maintained no insects for 10 months, so that PH3 fumigation was not needed any more that year.