Abstract :
In the paper it is suggested that for electronegative gases, where both ionizing and attachment processes occur, the condition for breakdown in uniform fields and the onset of discharges, which may lead to complete breakdown in certain circumstances, in non-uniform fields (with the positive electrode in the high-field region) is that the ionizing and attachment coefficients have the same value. In non-uniform fields and above a certain critical pressure pc the breakdown and discharge inception stresses coincide, but below pc they differ; the gaps processes operating in these regions are briefly discussed.