Microbiological Contamination: Evaluation of Some Sampling and Laboratory Analytical Methods

The limitations and problems of representative sampling in naval fuel tanks have been investigated. Problems have been associated with access, with possibly atypical habitats (for example, entrained sounding tube or drain line samples), and with types of samplers available. In laboratory bottle scale trials for biocide efficacy, microbial interface growth has been quantified by biochemical determination of cellular protein following alkali extraction. This method is applicable to frozen stored samples. The significance of mixed microbial populations, in relation to coalescer impairment and to biocide treatment of the fuel, is also discussed.