The face mask supplied with NebuChamber^® is contoured to the face of a young child. Although preferred during ideal conditions, the preformed shape may not fit all faces of infants. Thus, in order to minimize leaks it is important that the face mask fit is checked, and if a good fit is not achieved, another face mask can be used. A smooth, round mask that provides a good fit to the mouth may be an alternative.

Reference

Amirav I. Infant aerosol holding chamber face masks: not all are born equal! Respir Care 2006;51(2):123-5.