Portable device for measuring the concentration of at least one component in a gas exhaled by a breath fluid

A portable device for measuring the concentration of at least one component in a gas exhaled by a breath fluid, comprising:

• a mouthpiece through which the breath fluid is exhaled,
• an enclosure incorporating:
• a measuring vessel,
• a measurement means for measuring the concentration of at least one component in a gas of the breath fluid flowing into the measuring vessel, an opening into which the mouthpiece) is installed,
• a first chamber located upstream of the measuring vessel and comprising an inlet through which the exhaled breath fluid enters said first chamber, a second chamber located upstream of the measuring vessel, said second chamber comprising:
• an inlet leading into the first chamber, an outlet in fluid communication with the measuring vessel and through which a portion of the exhaled breath fluid passes, and
• an outlet leading to the ambient air, through which a portion of the exhaled breath fluid is expelled into the ambient air, wherein
• the second chamber is placed inside the first chamber or in a position adjacent to said first chamber,
• the outlet to the ambient air leads into the first chamber in such a way that only a portion of the exhaled breath fluid flowing into said first chamber enters the second chamber through the inlet of said second chamber, the other portion of the exhaled breath fluid being expelled into the ambient air,
• the measuring vessel is made from a pliable, flexible substrate made in the shape of a tube, the pliable, flexible substrate comprises a first side and a second side, and said sides are opposite each other,
• the first side is covered with a reflective metal material forming an optical reflection layer, and
• the pliable, flexible substrate incorporates a resistive heating element and said heating element is in the form of a flexible electrical circuit into which are integrated one or more heating filaments in the form of strips of metal arranged on the second side.