ELECTROMECHANICAL GAS DETECTION SENSORS (CiTiceLs) FOR MEASURING THE CONCENTRATION OF A SPECIFIC GAS OR GASES. THE SENSORS ARE BATTERY-SIZED COMPONENTS. SENSORS OPERATE ON AN ELECTROMECHENICAL PRINCIPLE, WHEREBY DIFFUSION OF THE TARGET GAS INTO THE SENSOR WILL INITIATE A CHEMICAL REACTION, RESULTING IN A SMALL ELECTRICAL CURRENT BEING GENERATED. THE ELECTRICAL CURRENT IS MEASURABLE AND PROPORTIONAL TO THE GAS CONCENTRATION. SENSORS ARE MANUFACTURED TO MEASURE SPECIFIC GAS TYPES.

GIR1 TERMS OF HEADING 9026 INCLUDES INSTRUMENTS AND APPARATUS FOR MEASURING OR CHECKING THE FLOW, LEVEL, PRESSURE OR OTHER VARIABLES OF LIQUIDS OR GASES. GIR6 TERMS OF ONE DASH SUBHEADING 902680, OTHER INSTRUMENTS AND APPARATUS. CN CODE 90268080, OTHER THAN ELECTRONIC.