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The One-Way Degassing Valve

One-way degassing valves are designed to allow pressure to be released from an airtight package while not allowing external atmosphere (i.e. air with 20.9% O2) to enter the package. A one-way degassing valve is useful for packaging products that are sensitive to oxygen and moisture and also release gas or entrapped air. The one-way degassing valve can be attached to a flexible package to relieve pressure built up in the package while protecting the interior contents from the damaging effects of oxygen and moisture.

When pressure inside a sealed package increases beyond the valve opening pressure, a rubber disk in the valve momentarily opens to allow gas to escape
out of the package.  As gas is released and the pressure inside the package drops below the valve close pressure, the valve closes.

Open/Release Mode	Air-Tight Closed Position
When pressure inside a sealed package increases beyond the valve opening pressure, the seal between the rubber disc and the valve body is momentarily interrupted and pressure can escape out of the package.	The CO2 pressure released from the fresh roasted coffee beans is low; therefore the valve is closed with an air-tight seal.