A breather device connects to a vessel. The breather device inlets air to the vessel and filters the air upon inlet via a filter media, and exhausts air from the vessel. The vessel has a pressure that may vary and a low pressure threshold and a high pressure threshold. The breather device includes a housing, a cartridge removable from the housing for containing the filter media, an inlet check valve to the housing, the inlet check valve is selectively biased to prevent flows therethrough unless the pressure in the vessel falls below the low pressure threshold, an outlet check valve from the housing, the outlet check valve is selectively biased to prevent exhaust therethrough unless the pressure in the vessel exceeds the high pressure threshold, and a pressure gauge connected to the housing for measuring internal pressure in the vessel. The breather device can additionally include seals and/or an internal check valve between the filter media and the vessel. The internal check valve, if present, prevents exhaust air of the vessel from contacting the filter media.

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