Section 866.5680 - Myoglobin immunological test system(a)Identification. A myoglobin immunological test system is a device that consists of the reagents used to measure by immunochemical techniques the myoglobin (an oxygen storage protein found in muscle) in serum and other body fluids. Measurement of myoglobin aids in the rapid diagnosis of heart or renal disease.(b)Classification. Class II (performance standards).