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Privacy and Security Notice

MiniOX Oxygen Meter

Instructions for use of MiniOX Responder Oxygen Detector


Calibration of the unit must be performed if the battery or sensor cell is replaced, or if the unit is dropped. Calibration should be performed in a fresh air environmnt. While the instrument is turned ON, press and hold both the Zero and Reset buttons; then, press the Power Peak button. The instrumnet will beep once. The descriptor "^Set" will appear on the display. The monitor then spans the instrument. When calibration is complete, the instrument beeps three times.

Turning On/OFF

To turn the instrument ON, simply press the Power/Peak button on the left-hand side of the display. All segments of the display will light upon turn-ON. To turn OFF the monitor, press and hold the Power/Peak button for five seconds. After a series of beeps, the display will turn off.

FAS (Fresh Air Setup)

Upon instrument turn-ON, the display will flash "FAS." While "FAS" flashes, pressing the Zero button will fresh air calibrate the instrument. The FAS will not be performed if the oxygen concentration is below 19.6%.

Gas Alarms

There are two levels of audible and visual alarms. The high or warning level alarms, indicating oxygen enrichment, are low-rate intermittent and non-latching. This is indicated by a "W" on the display and a beep approximately every five seconds. The factory default for the "W" alarm is 22% O2. The low alarm, indicating oxygen deficiency, is high-rate intermittent and latching. This is indicated by an "A" on the display and a beep approximately every 1/2 second. The alarm level can only be reset once the oxygen concentration rises above the alarm level. The factory default for the "A" alarm is 19.5% O2.

Low Battery Alarm

The low battery alarm occurs when a minimum of 24 hours of battery life remains. This is indicated by a "B" on the display and a beep approximately every 40 seconds.

Installing/Replacing the Battery

Remove belt clip by pressing the two tabs near the top and releasing from the back. Remove the two slotted head screws on the back of the case, located under the clip. Remove the 9-V battery from the snap connector and replace with a fresh 9-V battery. Replace the battery cover and the two slotted screw; snap the belt clip back. Wait one minute before turning the instrument ON and zeroin it. The instrument will not turn on for 45 seconds. The backlight is ON and --- is displayed during this period.

Calibration Check

If the unit continues to alarm after zeroing, press and hold both the zero and reset buttons. While holding the zero and reset buttons press and release the power/peak button. The unit will emit a single peak and set will appear on the display. The monitor will go through a series of beeps while it is being set. The calibration check is complete when "set" is no longer displayed and the unit reads 20.8% - 21.0%.

Replacing Sensor Assembly

The sensor assembly needs to be change on a yearly basis. A sticker located on the unit will indicate the date that the new sensor was installed, one year from that date a new sensor should be installed. If there are problems or questions regarding the sensor contact a member of the Safety Lab.