This study explored the effects of noise on medical staff in intensive care units (ICUs) in China during the COVID-19 pandemic. Firstly, noise levels were measured for 24 hours measured in four ICUs and noise sources were identified. Secondly, online questionnaire surveys were conducted to analyse the self-rated vocal perception of the ICU nurses who wore face masks. Participants were recruited from four ICUs and a total of 100 nurses from each ICU took part in the surveys. Lastly, the voice-related parameters were measured by using a monitor in four ICUs. For this, a non-invasive accelerometer was attached to a participant’s neck during working hours. The noise levels in the ICUs exceeded the WHO recommended values. The most frequent voice symptom was the ‘dryness in the throat’ and followed by the ‘difficulty in being heard’ ‘The voice levels of the nurses were not much influenced by the background noise levels.