Abstract: An apparatus and method to analyze fluid degradation in a closed system is disclosed. The method includes collection of a sample fluid from the closed system. The sample fluid collected is maintained at a sample fluid pressure, which is substantially equivalent to a pressure of the closed system. Thereafter, a change of a volume of the sample fluid is caused, which generates a change in the sample fluid pressure. A series of sample fluid pressures and volumes of the sample fluid are taken. Next, a bulk modulus of the sample fluid is determined. The bulk modulus of the sample fluid is compared with a baseline bulk modulus. Lastly, the method involves generation of a communication when the bulk modulus of the sample fluid breaches a tolerance.