The leakage of protective masks remains a problem that cannot be ignored in clinical practice, and the insufficient protection caused by the leakage can lead to unnecessary occupationally acquired respiratory tract infections.

This study aimed to identify the factors influencing nursing staff's adherence to wearing medical protective masks through behavioural intervention. A quantitative fit test was conducted to assess the effectiveness of the intervention, providing guidance for correct mask usage among nursing staff.

A sample of 40 nurses from the International Peace Maternity and Child Health Hospital of the China Welfare Institute was selected to observe three different methods of wearing medical protective masks, followed by a behavioural intervention. The quantitative fit test was administered before and after the intervention, recording the passing rate of medical protective masks.

A pithy formula combined with a fit test can promote the correct rate of mask wearing and improve protection. The compatibility and comfort of the mask model with the wearer's head and face size will affect the effectiveness and compliance of mask use.

Pithy formula intervention and the use of fit test combined with dynamic scene simulation evaluation provided a scientific and operational solution for improving the pass rate of mask wearing and promoted the paradigm shift from ‘static compliance’ to ‘dynamic adaptation’ in the field of respiratory protection.