UI Oxygen Sensor Gauging Tape System for Petroleum Tankers and Inland Barges


Includes Built-In Auto-Calibration Feature
The system's sensing probe (above, left) travels down the barrel of the gauging tape unit (above, center) through a vapor-control valve and into the void of the tank below. There, it quickly measures and displays (above, right) the percentage of oxygen found in the environment above the liquid product.

The MMC Flexi-Dip Oxygen Sensor Gauging Tape is a battery-operated electronic system featuring the latest in solid-state circuitry and an easy-to-view LCD readout panel. A built-in auto-calibration feature allows the unit to automatically calibrate to 20.9%. It offers a fast, safe and convenient method for measuring oxygen content within the ullage space of a closed tank--the space between the top of the tank and the liquid cargo below. The precise measurement of void space oxygen levels is a crucial consideration for petroleum-carrying vessels which blanket their liquid cargos with inert gas to prevent combustion and explosion. In order to maintain the proper inert gas conditions aboard tanker ships, oxygen levels must be minimized and, according to U.S. Coast Guard regulations in the United States, monitored and documented.

The Flexi-Dip Oxygen Sensor Gauging Tape system measures the oxygen level without aspiration and its associated cumbersome sampling hose and weighted head piece. The operator can auto-calibrate the tape before it is inserted into the vapor-control valve and locked in place. Then the valve is opened and the tape sensor is lowered either one meter below deck level or to 50% of ullage space level. The digital LCD display in the hub of the device indicates the percentage of oxygen present. If the oxygen content exceeds 8% of the inert gas level in ullage space, audio and visual warning alarms in the unit are triggered.


  • - Over 1% to 25% Range: +/- 0.2%
  • - of Sensor Positioning: +/- 1/8"
  • - of linear tape: +/- 1/8" (3mm), +/- 0.01% of F.S. tape LGT (F.S. = Full Scale).

Oxygen Sensor Measurement Range: 0% to 25%

Battery: 9-Volt Duracell MN1604.

Tape Lengths: Standard 50 ft. (15m), Optional 100 ft. (30m).

Hazardous Environmental Protection: Intrinsically safe.

Approvals: BASEEFA and Factory Mutual (pending).