Mass administration of oxygen, Middlesex Hospital, Mortimer Street, Westminster, Greater London
Patients wearing 'B.L.B. masks' which are fed from the central control of the R.A.F. equipment for the multiple administration of oxygen. A 'B.L.B. mask' allowed the administration of oxygen in concentrations ranging from that in air to pure oxygen. It used a mechanically simple and easy to operate device. The mask was also more comfortable and allowed patients to eat and speak whilst wearing it. It was worn by pilots on commercial American airlines, and used in the delivery of oxygen at high altitudes.