Before starting the procedure the set up time of each bronchoscope will be recorded. The view, image, and light of each bronchoscope will be assessed, then the inspection of the upper lobe segmental bronchi will be conducted. The time of lavage and suctioning until no more specimen can be collected will be measured. The volume of the obtained specimen will be measured. The specimen will be evaluated by a blinded observer after the procedure is completed.(clear fluids, mucous secretions, viscous secretions, pus, blood etc). The blinded observer will evaluate the quality and quanity of the sample for obtaining cultures.The blinded observer will be an attending or resident from the infectious disease department.