Gas densimeter

A gas densimeter configured for monitoring a pressure or density of a gas in a gas chamber, the gas densimeter comprising:

• a housing having a first housing chamber and a measuring chamber;
• a first coupling, via which the measuring chamber is connectable to the gas chamber, the measuring chamber having a gas-permeable connection to the gas chamber via the first coupling;
• a reference bellows that is connected directly or indirectly to a transmission element, the reference bellows forming a reference chamber filled with a constant amount of a reference gas;
• at least one transmitting and/or monitoring unit that is operatively connected directly or indirectly to the transmission element;
• and
• a surface section covering the reference bellows and that is reachable at least partially within the first housing chamber or measuring chamber, the surface section being a measuring surface for the gas from the gas chamber,
• wherein the surface section covering the reference bellows has an effective measuring surface, the effective measuring surface being smaller by 2% to 80% than a cross-sectional area of the reference bellows or the surface section covering the reference bellows.