The invention relates to a method for detection of non-zero-voltage switching operation of a lamp ballast, which has a half-bridge circuit with a first and a second semiconductor switching element, a resonant tuned circuit which is connected to one output of the half-bridge circuit, and a snubber capacitance, which is connected in parallel with one of the semiconductor switching elements. The method has the following method steps: provision of a voltage measurement signal (Vs) which is dependent on a voltage at the output of the half-bridge, evaluation of the voltage measurement signal (Vs) in each case before switching-on times of at least one of the first and second semiconductor switching elements by comparison of the voltage measurement signal (Vs) with a reference value (Vref) for detection of the non-zero-voltage switching operation. The invention also relates to a ballast for carrying out a method such as this.