Given the traditional commitment of trade unions to occupational health and safety standards, unions might have been expected to be strongly involved in containing the Covid-19 pandemic. This article focuses on their policy positions at national and sectoral level towards the occupational health and safety measures taken to limit the spread of Covid-19 in Germany, France and Luxembourg from the beginning of the pandemic in March 2020 until the surging fourth wave of infections in November–December 2021. The authors’ data show that unions have found it increasingly difficult over the course of the pandemic to develop policy positions in the domain of occupational health and safety that address the variegated situations and needs of their different member groups and that achieve a balance between membership logics and public health considerations.