Abstract: Background: Use of noninvasive ventilation (NIV) has extended beyond intensive care units (ICUs), becoming usual practice in emergency departments (EDs) and general wards. Objective: To analyse the relationship between nursing care and NIV outcome in different hospital units. Methods: Treatment success/failure, interface intolerance and complications were evaluated according to patient characteristics, nursing care provided, and procedures used. Complications analysed included bronchoaspiration, pneumothorax, skin lesions, inability to manage secretions, eye irritations, deteriorating level of consciousness, gastric distension, and excessive air losses around the mask. Results: Of 387 patients, 194 (50.1%) were treated in ICU, 121 (31.3%) in ED, 38 (9.8%) postsurgery, and 34 (8.8%) in general wards. Regression analysis, adjusted for APACHE score and NIV indication, showed 3.3 times greater risk of NIV failure [95% CI (1.2-9.2) ] in a university-hospital ICU with <50 NIV cases/year, compared to a community hospital ICU. In ICUs and general wards, NIV was suspended in 12% of patients due to interface intolerance. Acute-on-chronic lung diseases (ACLD) had lower risk of NIV failure [OR 0.2, 95% CI (0.06-0.69) ] and lack of humidification was not associated with treatment failure [OR 0.2, 95% CI (0.1-0.4) ]. Poor secretion management was linked to pneumonia [OR 2.5, 95% CI (1.1-5.9) ] and early weaning/extubation [OR 3.3, 95% CI (1.2-8.9) ]. Interface intolerance was associated with conventional ICU ventilators [OR 4.4, 95% CI (2.1-9.2) ] and nasal skin lesions with excessive air losses [OR 2.4, 95% CI (1.1-5.3) ], especially with oronasal masks [OR 3.5, 95% CI (1.1-11.3) ]. Conclusion: Acute respiratory failure patients with pneumonia admitted to general wards had increased interface intolerance and NIV failure. Rotating mask types could improve NIV success in any unit administering this therapy.