Conidia Bioscience FUELSTAT®
Marine and Land Diesel Test Kit
In response to calls from marine and land based operators, in particular the navies, for a real-time test for microbial contamination in diesel fuel systems and tanks, Conidia Bioscience developed the FUELSTAT® Test Kit for use on marine and land based diesel fuels.
The objective of the test is to provide rapid on site screening of fuels or the water from the bottom of a tank (the water phase can hold a thousand times more microbes than the fuel), giving a quick and accurate assessment of H.res (the ‘Diesel Bug’), bacteria and other fungi (moulds & yeasts) in the fuel tank.
The FUELSTAT® Test kit does not utilise the traditional growth-based methods employed by laboratories and all other “rapid” tests currently on the market, which require a minimum of 72 hours to provide any results. FUELSTAT® is an immunoassay test (rather like a pregnancy test, but hundreds of times more sensitive). This means that it detects contamination by “finding” material that is produced by the 3 different types of contaminants that grow in the fuel. Therefore, there is no need to capture part of the living organism to grow it up.
This is important as the main fungus the test detects, Hormoconis resinae (H.res) or “The Diesel Bug” does not just float around at the fuel/water interface like the other microbes; it actually sticks to the bottom or sides of the tank. This style of testing is also important as the “produced material” from the organisms is spread throughout the liquid in the tank, not just at the interface. Therefore, there is a better chance of finding that “produced material” in a small sample. The result is a more accurate and consistent answer.
The FUELSTAT® Test kit measures by wet weight the amount of different types of live contamination i.e. H.res, bacteria and other fungi (moulds & yeasts) actively growing in the sample. This is a newer, more accurate measurement system than the old Colony Forming Unit (CFU) count, which is still in common use.
The test provides results based on a traffic light scenario:
– Negative (green light) – negligible contamination
Fuel – Below 4,000 cfu/l or 150 μg/l
Water – Below 1,000 cfu/ml or 33 μg/ml
– Low Positive (amber light) – moderate contamination
Fuel – 4,000 – 20,000 cfu/l or 150 – 750 μg/l
Water – 1,000 – 10,000 cfu/ml or 33 – 166 μg/ml
– High Positive (red light) – heavy contamination
Fuel – Above 20,000 cfu/l or 750 μg/l
Water – Above 10,000 cfu/ml or 166 μg/m
The Test Kit:
Packaged in a foil pouch that is split in two, each FUELSTAT® Test Kit contains a 3n1 test paddle and pipette (chemical dropper) in one section and a sample preparation bottle (a sealed 160ml plastic bottle containing 3.0ml of blue extraction buffer), a “dropper cap” and instructions for use in the other section.
The test paddle utilises lateral flow technology (wicking) and antibodies to detect the three groups of micobial contaminants found to grow in middle distilate fuels – Aviation Kerosene, Diesel and Biodiesel.
Test Kit Laid Out FUELSTAT Test Paddle
The test paddle has six (6) Lateral Flow Devices (LFD’s) included in each 3n1 test:
Level 1 (LOW) 3 devices with cut off levels for H.res, bacteria and other fungi at a level derived from IATA Guidance Material where the microbes have established themselves as a consortium and a fuel treatment is required. At this level the consortium is generally undetectable to the human eye.
Level 2 (HIGH) 3 devices with cut off levels for H.res, bacteria and other fungi at a level derived from IATA Guidance Material where the microbes are growing so rapidly, or have been growing for a long time, that they may be causing damage to the structure of the tank or are likely to cause filter blockage and component failure. This level of contamination requires tank cleaning and fuel treatment before it causes further damage. At this level biomass should be very visable in the filtration/water seperation system or on the bottom of the tank.