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1. The ordinary buzzer can be directly installed in the explosion-proof distribution box (explosion-proof type), which does not affect the explosion-proof performance of the explosion-proof distribution box. However, because the flameproof distribution box is tightly sealed, the sound emitted by the buzzer is difficult to spread. To solve this problem, only holes can be opened on the explosion-proof distribution box, and explosion-proof and sound transmission can be achieved through the explosion-proof network (control the number of mesh and layers) or powder metallurgy sheet (control the number of mesh and thickness), but this has an impact on the loudness, and it is difficult to achieve in the explosion-proof structure. The standard is gb3836.2

2. A more convenient way is to make the buzzer a cost safe explosion-proof product according to the standard gb3836.4. In this way, it can be placed somewhere outside.