Annoyance of low-level tonal sounds – A penalty model

•Tonal sounds can be more annoying than non-tonal sounds.•Penalty is applied in many countries to consider the annoyance of tonal sounds.•Penalty means that a certain dB value is added over the measured dB value.•Data from a recent study was used to develop a penalty prediction model.•The model needs further validation from future psychoacoustic experiments.