The Teledynes 3350 is an Oxygen (O2) monitor developed by TAI. It is specifically designed for control room purposes. This monitor provides accurate measurements of oxygen concentrations in control rooms, enclosed atmospheres, critical breathing circuits, and other uses in need of ambient air monitoring. Measuring of oxygen concentrations is needed in ever industry for safety purposes and for assurance that there is enough oxygen in a closed place. Furthermore, this monitor can be used and maintain simply.