Abstract Background: Neonatal resuscitation training is considered to be multifarious and includes manual ventilation as an essential competence for any health-care provider. Usually, ventilation is applied with self-inflating bags (SIBs). These devices have been shown to produce highly variable, operator-dependent peak inspiratory pressures (PIPs) and tidal volumes (V_T). Excessive PIP and V_T contribute to lung injury. We studied a simple tool to improve resuscitation skills. Objective: The objectives of this study were to train health-care providers to avoid excessive PIP and V_T by visualizing these values by using a respiratory function monitor (RFM) and to study the sustainability of such a training. Material and methods: Previously untrained medical professionals were educated and trained to ventilate a neonatal preterm manikin. PIP and V_T were measured with an RFM. Graphical representations of the measurements were displayed during training, but the RFM was blinded during subsequent recordings. Participants were reassessed directly after training and 1 month later. Results: In total, 37 participants were trained and assessed three times during the study. Median PIPs (range) were 32.3 (4.1–44) cm H₂O before training, 17.8 (9.6–23.6) cm H₂O directly after training (P<0.05), and 18.7 (7.5–41.6) cm H₂O 1 month later, and the values remained low, compared with before training (P<0.05). Median V_Ts were 6.7 (4.2–44) mL before training, 3.5 (1.8–7.3) mL directly after training (P<0.05), and 4.1 (1.9–9.7 mL) 1 month after training (P<0.05). Conclusion: Using a SIB, untrained staff produced excessive PIP and V_T. Training with a simple RFM significantly reduced the occurrence of excessive PIP and V_T. The effect was sustained for at least 1 month.