The use of nebulisers was assessed in four hospitals. Nebulisers were checked in use and medical and nursing staff were interviewed. All but one nebuliser was driven by 100% oxygen and only 3 of 111 interviewees preferred air for patients with hypercapnia. In 5 of 44 nebulisers in use, water was used as the dilutant. The calculated times for complete nebulisation of the solutions ranged from 3.5 to 117 min. The results of this survey illustrate a need for better education concerning the use of nebulisers in hospitals.