Test tubes with color coded tops indicate the additive contained in the tube.  In the DIRECTORY OF TESTS the color-coding is indicated as well as the volume of blood sample required for each test.  When collecting blood samples it is important to allow the tube to fill completely and to follow the "order of draw" for tubes as indicated in the Order of Draw Chart.

See Inpatient Requisition - Lab Req I and Specimen Requisition - Lab Req II for additional reference to tube type and specimens required for testing.