The aim of NEU-CAP is to investigate the clinical impact of using a colorimetric carbon dioxide (CO₂) detector during non-invasive ventilation (NIV). Infants born before 32 weeks of gestation will be included in this trial. This is a stepped-wedge cluster randomised controlled trial. The participating centre, rather than the individual infant, will be the unit of randomisation. This design is appropriate to test the effect of an intervention that encompasses a behavioural aspect, in this case CO₂-detector-guided non-invasive ventilation.