Neubulisation, bronchoscopy induced sputum collection and face mask ventilation should be avoided as far a possible. If medically indicated, they should be undertaken in a negative pressure room with minimal but adequate staffing. All staff should be in PPC covering the torso, arms and hands as well as eyes, nose and mouth. N95s, N-99s or N-100s are adequate but full face masks are desirable. However, the use of powered air purifying respirators is not recommended because of risk to self and environmental contamination. The use of a face mask with a good fit and attached valved manifold may reduce the risk of transmission. 35 No infection has been attributed to the taking of nasopharyngeal aspirate from SARS patients in Hong Kong. When performed it should be taken in a single room while wearing full PPC. A new upper respiratory tract irrigation method has been devised to replace nasopharyngeal aspirate testing, which should be safer. 36 The disadvantage of this method is that it cannot be used in young children.