Gas sensor and gas sensor cartridge

A gas sensor comprising:

• a gas sensor cartridge;
• a gas sensor body to which the gas sensor cartridge is detachably attached;
• and
• a light source provided inside the case,
• wherein the gas sensor cartridge includes:
• a case that has an intake port and an exhaust port and serves as a gas sensor chamber;
• a gas sensor device provided inside the case;
• an external connection terminal provided at the case and connected to the gas sensor device;
• a first sealing member that seals the intake port such that the intake port is opened when the gas sensor cartridge is attached to the gas sensor body;
• and a second sealing member that seals the exhaust port such that the exhaust port is opened when the gas sensor cartridge is attached to the gas sensor body.