Sampling for Water and Microbial Growth Management
Regular fuel sampling for visual signs of microbial growth,
checking the fuel system for corrosion and testing for microbes is am
imperative especially when free water is found in the system. If bottom samples
reveal water, then the likelihood of microbial contamination is almost certain.
If the fuel itself is found to be cloudy, dark or both then fuel degradation
has reached a critical stage and immediate action needs to take place.
The combination of water in the tank, moderate to severe
corrosion on system parts and cloudy or dark fuel indicates poor fuel quality.
When fuel visually looks good it can be difficult to determine whether there is
something else lurking. That is why microbial testing is so important. If it is caught early then biocides can be
used to kill the infection and reduce the degradation process and the potential
for system damage. Monitoring for microbial contamination is a necessary part
of maintaining fuel quality. Field tests are an economical way of providing the
Bottom Sampling Basics
All fuel analysis requires proper fuel sampling. Generally,
samples should be taken from the lowest point in the tank using a bottom
sampler like the one shown below.
Additionally, samples can be taken mid-tank or upper-tank to
determine the visual quality of the fuel and to test. When sampling fuel, a stainless or aluminum
construction is preferred. Brass samplers can effect test results as the metal
reacts with fuel. Porous materials are
also not recommended. When sampling, use clear glass jars for visual inspection
of the fuel. There are limitations to sampling. A spot sample only provides a
sampling from one particular point in the tank. However limited, sampling
remains the best approach to determine what is in your tank.