First responders' perceived and actual competence in tunnel fire safety

•Quantitative study of first responders' perceived competence in tunnel fire safety.•Qualitative study of first responders' actual competence in tunnel fire safety.•First responders' perceived competence is discussed against their actual competence.•First responders' self-reported competencies predict inaccurately the real competencies of the fire and rescue services.•Competence-enhancing activities are necessary to improve first responders' actual competencies in tunnel fire safety.