What are the specific air tightness standards for ventilation doors in GJB2805B-2021?

According to GJB2805B-2021 "Technical Requirements for Anti-Theft in Ordnance Warehouses," the air tightness requirements for ventilation doors are as follows:

I. Air Tightness Requirements

The air tightness of ventilation doors must meet the Grade 8 requirements of the GB/T7106-2019 standard.

II. Explanation of Air Tightness Standards

GB/T7106-2019 "Test Methods for Air Permeability, Water Tightness, and Wind Resistance of Building External Windows and Doors" specifies the testing methods for the air tightness performance of building external windows and doors. The air tightness performance test is conducted using the air collection box method, primarily by measuring the air infiltration of windows and doors under a certain pressure difference to evaluate their air tightness performance.

III. Protective Functions of Ventilation Doors

In addition to meeting air tightness requirements, ventilation doors must also possess the following protective functions:

1. Insect, Bird, and Rodent Prevention: Prevents external insects, birds, rodents, etc., from entering the warehouse.

2. Moisture and Dust Prevention: Prevents materials in the warehouse from becoming damp and dust from entering.

3. Fire, Theft, and Explosion Prevention: Enhances the security of the warehouse.

IV. Structural Design

The structural design of ventilation doors should be reasonable, ensuring both ventilation effectiveness and meeting anti-theft and protective requirements. For example, a three-layer sealed ventilation window design can be adopted, combining both ventilation and protective functions.

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