Blood collection tubes are made of glass and pet tubes and color coded according to the appropriate additive and international standard. Each tube had its own vacuum state for collection of blood with proper quantity and marked on lable for blood collection and additives inside of the tube.
COLOR CODE:
PLAIN TUBE: RED CAP NO ADDITIVE
PRO-Coagulation tube: red cap
Clot Activator:orange cap
Gel and Clot Activator tube:yellow cap
EDTA K2/K3:Purple Cap
Coagulation tube(9NC TUBE): blue cap 3.2% Sodium citrate
Coagulation tube (ESR TUBE): black cap 3.8% Sodium citrate
Heparin tube(Sodium heparin / lithium heparin):green cap ,
Glucose tube:grey cap Sodium Fluoride+EDTA or Potassium oxalate