Oxygen:

Oxygen utilized for cutting operations should have a purity of 99.5 % or higher. Lower purity decreased the efficiency of the cutting operation. A one percent decrease in oxygen purity to 98.5 % will result in reduction in cutting speed of about 15 percent, and an increase of approximate 25 percent in consumption of cutting oxygen. The quality of the cut shall be impaired, and the amount and tenacity of the adhering slag shall increase. With oxygen purities below 95 %, the familiar cutting action disappears, and it becomes a melt and washes action that is typically unacceptable.