To obtain a sputum specimen. the client should rinse the mouth to prevent contamination. breathe deeply. and then cough unto a sputum specimen container. The client should be encouraged to cough and not spit so as to obtain sputum. Sputum can be thinned by fluids or by a respiratory treatment such as inhalation of nebulized saline or water. The optimal time to obtain a specimen is on arising in the morning.