14-54 Figure 14-99.  A capture solution is put into a 1 liter sample of fuel  and shaken. The solution is then put into the analyzer shown to  determine the level of microorganisms in the fuel. Figure 14-97.  All entry points of fuel into the aircraft are marked  with the type of fuel to be used. Never introduce any other fuel into  the aircraft other than that which is specified.  Figure 14-98.  This kit allows periodic testing for water in fuel.  The presence and level of microorganisms in a fuel tank  can also be measured with a field device. The test detects  the metabolic activity of bacteria, yeast, and molds,  including sulfate reducing bacteria, and other anaerobe  microorganisms. This could be used to determine the amount  of anti-microbial agent to be added to the fuel. The testing  unit is shown in  Figure 14-99.