1、Designation: D 6469 04An American National StandardStandard Guide forMicrobial Contamination in Fuels and Fuel Systems1This standard is issued under the fixed designation D 6469; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the
2、year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This guide provides personnel who have a limitedmicrobiological background with an understanding of thesympto
3、ms, occurrence, and consequences of chronic microbialcontamination. The guide also suggests means for detectionand control of microbial contamination in fuels and fuelsystems. This guide applies primarily to gasoline, aviation,boiler, industrial gas turbine, diesel, marine, and furnace fuels(see Spe
4、cifications D 396, D 910, D 975, D 1655, D 2069,D 2880, D 3699, D 4814, and D 6227) and fuel systems.However, the principles discussed herein also apply generallyto crude oil and all liquid petroleum fuels. ASTM Manual 472provides a more detailed treatment of the concepts introducedin this guide; it
5、 also provides a compilation of all of thestandards referenced herein that are not found in the AnnualBook of ASTM Standards, Section Five on Petroleum Productsand Lubricants.1.2 This guide is not a compilation of all of the concepts andterminology used by microbiologists, but it does provide agener
6、al understanding of microbial fuel contamination.1.3 The values in SI units are to be regarded as the standard.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safe
7、ty and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:3D 130 Test Method for Detection of Copper Corrosion fromPetroleum Products by the Copper Strip Tarnish TestD 396 Specification for Fuel OilsD 445 Test Method for
8、 Kinematic Viscosity of Transparentand Opaque Liquids (the Calculation of Dynamic Viscos-ity)D 515 Test Methods for Phosphorus in Water4D 664 Test Method forAcid Number of Petroleum Productsby Potentiometric TitrationD 888 Test Methods for Dissolved Oxygen in WaterD 910 Specification for Aviation Ga
9、solinesD 974 Test Method for Acid and Base Number by Color-Indicator TitrationD 975 Specification for Diesel Fuel OilsD 1067 Test Methods for Acidity or Alkalinity of WaterD 1126 Test Method for Hardness in WaterD 1293 Test Methods of pH of WaterD 1298 Test Method for Density, Relative Density (Spec
10、ificGravity), or API Gravity of Crude Petroleum and LiquidPetroleum Products by Hydrometer MethodD 1331 Test Methods for Surface and Interfacial Tension ofSolutions of Surface-Active AgentsD 1426 Test Methods for Ammonia Nitrogen in WaterD 1655 Specification for Aviation Turbine FuelsD 1744 Test Met
11、hod for Water in Liquid Petroleum Prod-ucts by Karl Fischer Reagent4D 1976 Test Method for Elements in Water by Inductively-Coupled Argon Plasma Atomic Emission SpectroscopyD 2068 Test Method for Filter Blocking Tendency of Dis-tillate Fuel OilsD 2069 Specification for Marine Fuels4D 2274 Test Metho
12、d for Oxidation Stability of DistillateFuel Oil (Accelerated Method)D 2276 Test Method for Particulate Contaminant in Avia-tion Fuel by Line SamplingD 2880 Specification for Gas Turbine Fuel OilsD 3240 Test Method for Undissolved Water in AviationTurbine FuelsD 3241 Test Method for Thermal Oxidation
13、 Stability ofAviation Turbine Fuels (JFTOT Procedure)D 3242 Test Method for Acidity in Aviation Turbine FuelD 3325 Practice for Preservation of Waterborne OilSamples1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products and Lubricants and is the direct responsibility
14、of SubcommitteeD02.14 on Stability and Cleanliness of Liquid Fuels.Current edition approved May 1, 2004. Published May 2004. Originallyapproved in 1999. Last previous edition approved in 1999 as D 646999.2MNL 47, Fuel and Fuel System Microbiology: Fundamentals, Diagnosis, andContamination Control, P
15、assman, F. J., ed., ASTM International, 2003.3For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.4Withdrawn.1Copy
16、right ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.D 3326 Practice for Preparation of Samples for Identifica-tion of Waterborne OilsD 3328 Test Methods for Comparison of Waterborne Petro-leum Oils by Gas ChromatographyD 3414 Test Method for
17、Comparison of Waterborne Petro-leum Oils by Infrared SpectroscopyD 3699 Specification for KerosineD 3867 Test Methods for Nitrite-Nitrate in WaterD 3870 Practice for Establishing Performance Characteris-tics for Colony Counting Methods in Microbiology4D 4012 Test Method for Adenosine Triphosphate (A
18、TP)Content of Microorganisms in WaterD 4057 Practice for Manual Sampling of Petroleum andPetroleum ProductsD 4176 Test Method for Free Water and Particulate Con-tamination in Distillate Fuels (Visual Inspection Proce-dures)D 4412 Test Methods for Sulfate-Reducing Bacteria inWater and Water-Formed De
19、positsD 4418 Practice for Receipt, Storage, and Handling of Fuelsfor Gas TurbinesD 4454 Test Method for Simultaneous Enumeration of TotalRespiring Bacteria in Aquatic Systems by MicroscopyD 4478 Test Methods for Oxygen Uptake4D 4814 Specification forAutomotive Spark-Ignition EngineFuelD 4840 Guide f
20、or Sampling Chain-of-Custody ProceduresD 4860 Test Method for Free Water and Particulate Con-tamination in Mid-Distillate Fuels (Clear and Bright Nu-merical Rating)D 4870 Test Method for Determination of Total Sediment inResidual FuelsD 4952 Test Method for Qualitative Analysis for ActiveSulfur Spec
21、ies in Fuels and Solvents (Doctor Test)D 5304 Test Method for Assessing Distillate Fuel StorageStability by Oxygen OverpressureD 5452 Test Method for Particulate Contamination in Avia-tion Fuels by Laboratory FiltrationD 6217 Test Method for Particulate Contamination inMiddle Distillate Fuels by Lab
22、oratory FiltrationD 6227 Specification for Grade 82 Unleaded AviationGasolineD 6426 Test Method for Determining Filterability of Distil-late Fuel OilsD 6974 Practice for Enumeration of Viable Bacteria andFungi in Liquid FuelsFiltration and Culture ProceduresE 177 Practice for the Use of the Terms Pr
23、ecision and Biasin ASTM Test MethodsE 1259 Test Method for Evaluation of Antimicrobials inLiquid Fuels Boiling below 390CE 1326 Guide for Evaluating Nonconventional Microbio-logical Tests Used for Enumerating Bacteria2.2 Energy Institute Standards:5IP 385 Determination of the Viable Microbial Conten
24、t ofFuels and Fuel Components Boiling Below 390CFiltration and Culture MethodIP Guidelines for the Investigation of the Microbial Contentof Fuel Boiling Below 390C and Associated WaterIP Proposed Method BY Determination of Fungal FragmentContent of Fuels Boiling Below 390C2.3 Government Standards:64
25、0 CFR 79 Fuels and Fuel Additives Registration Regula-tions40 CFR 152 Pesticide Registration and Classification Pro-cedures2.4 Other Standards:7Test Method 2540 D. Total Suspended Solids Dried at103105C3. Terminology3.1 Definitions:3.1.1 aerobe, nan organism that requires oxygen to re-main metabolic
26、ally active.3.1.1.1 DiscussionAerobes use oxygen as their terminalelectron acceptor in their primary energy-generating metabolicpathways. Aerobes require oxygen for survival, using aerobicmetabolic processes to generate energy for growth and sur-vival.3.1.2 aggressiveness index (A.I.), nthe value co
27、mputedfrom the sum of the pH + log alkalinity + log hardness of watersample where both alkalinity and hardness are reported asmilligram CaCO3L.3.1.2.1 DiscussionAsA.I. decreases, water becomes morecorrosive. At A.I. $ 12, water is noncorrosive. At 10 #A.I. 13.0. Potentialfood sources range from sing
28、le carbon molecules (carbondioxide and methane) to complex polymers, including plastics.Oxygen requirements range from obligate anaerobes, which5Available from Energy Institute, 61 New Cavendish St., London, WIG 7AR,U.K6Available from U.S. Government Printing Office, Superintendent of Docu-ments, 73
29、2 N. Capitol St., NW, Mail Stop: SDE, Washington, DC 20401.7Available from American Public Health Association, 800 I Street, NWWashington, DC 20001.D6469042die on contact with oxygen, to obligate aerobes, which die ifoxygen pressure falls below a species specific threshold.3.1.7 bioburden, nthe leve
30、l of microbial contamination(biomass) in a system.3.1.7.1 DiscussionTypically, bioburden is defined interms of either biomass or numbers of cells per unit volume ormass or surface area material tested (g biomass / mL; gbiomass / g; cells / mL sample, and so forth). The specificparameter used to defi
31、ne bioburden depends on critical prop-erties of the system evaluated and the investigators prefer-ences.3.1.8 biocide, na poisonous substance that can kill livingorganisms.3.1.8.1 DiscussionBiocides are further classified as bac-tericides (kill bacteria), fungicides (kill fungi), and microbio-cides
32、(kill both bacterial and fungi). They are also referred toas antimicrobials.3.1.9 biodeterioration, nthe loss of commercial value orperformance characteristics, or both, of a product (fuel) ormaterial (fuel system) through biological processes.3.1.10 biofilm, na film or layer of microorganisms,biopo
33、lymers, water, and entrained organic and inorganic debristhat forms as a result of microbial growth and proliferation atphase interfaces (liquid-liquid, liquid-solid, liquid-gas, and soforth) (synonym: skinnogen layer).3.1.11 biomass, ndensity of biological material per unitsample volume, area, or m
34、ass (g biomass/g(or/mLor/cm2)sample).3.1.12 biosurfactant, na biologically produced moleculethat acts as a soap or detergent.3.1.13 consortium (pl. consortia), nmicrobial communitycomprised of more than one, species that exhibits propertiesnot shown by individual community members.3.1.13.1 Discussio
35、nConsortia often mediate biodeteriora-tion processes that individual taxa cannot.3.1.14 depacifying, adjthe process of removing hydrogenions (protons) from the cathodic surface of an electrolytic cell,thereby promoting continued electrolytic corrosion.3.1.15 deplasticize, vthe process of breaking do
36、wn poly-mers in plastics and similar materials, resulting in loss of thematerials structural integrity.3.1.16 facultative anaerobe, na microorganism capable ofgrowing in both oxic and anoxic environments.3.1.16.1 DiscussionFacultative anaerobes use oxygenwhen it is present, and use either organic or
37、 inorganic energysources (nitrate, sulfate, and so forth) when oxygen is depletedor absent.3.1.17 fungus (pl. fungi), nsingle cell (yeasts) or filamen-tous (molds) microorganisms that share the property of havingthe true intracellular membranes (organelles) that characterizeall higher life forms (Eu
38、karyotes).3.1.18 metabolite, na chemical substance produced byany of the many complex chemical and physical processesinvolved in the maintenance of life.3.1.19 microbial activity test, nany analytical proceduredesigned to measure the rate or results of one or moremicroorganism processes.3.1.19.1 Dis
39、cussionExamples of microbial activity testsinclude loss or appearance of specific molecules or measuringthe rate of change of parameters, such as acid number,molecular weight distribution (carbon number distribution),and specific gravity.3.1.20 microbially induced corrosion (MIC), ncorrosionthat is
40、enhanced by the action of microorganisms in the localenvironment.3.1.21 mold, nform of fungal growth, characterized bylong strands of filaments (hyphae) and, under appropriategrowth conditions, aerial, spore-bearing structures.3.1.21.1 DiscussionIn fluids, mold colonies typically ap-pear as soft sph
41、eres; termed fisheyes.3.1.22 obligate aerobe, nmicroorganism with an absoluterequirement for atmospheric oxygen in order to function.3.1.22.1 DiscussionObligate aerobes may survive periodsin anoxic environments but will remain dormant until sufficientoxygen is present to support their activity.3.1.2
42、3 obligate anaerobe, nmicroorganism that cannotfunction when atmospheric oxygen is present.3.1.23.1 DiscussionObligate anaerobes may survive peri-ods in oxic environments but remain dormant until conditionsbecome anoxic.3.1.24 oxic, adjan environment with a sufficient partialpressure of oxygen to su
43、pport aerobic growth.3.1.25 shock treatment, nthe addition of an antimicrobialagent sufficient to cause rapid and substantial (several orders ofmagnitude) reductions in number of living microbes in a fluidor system receiving that concentration.3.1.26 skinnogen, nsynonymous with biofilm.3.1.26.1 Disc
44、ussionGenerally applied to a biofilm formedat the fuel-water interface.3.1.27 sour, vto increase the concentration of hydrogensulfide.3.1.28 sulfate reducing bacterial (SRB), pl., nany bacteriawith the capability of reducing sulfate to sulfide.3.1.28.1 DiscussionThe term SRB applies to representa-ti
45、ves from a variety of bacterial taxa that share the commonfeature of sulfate reduction (SO4=to S=). SRB are majorcontributors to MIC.3.1.29 taxa, pl., nthe units of classification of organisms,based on their relative similarities.3.1.29.1 DiscussionEach taxonomic unit (group of organ-isms with great
46、est number of similarities) is assigned, begin-ning with the most inclusive to kingdom, division, class, order,family, genus, and species. Bacteria and fungi are often furtherclassified by strain and biovariation.3.1.30 viable titer, nthe number of living microbespresent per unit volume, mass, or ar
47、ea.3.1.30.1 DiscussionViable titer is reported in terms ofeither colony forming units (CFU) or most probable number(MPN) per millilitre, milligram, or centimetre squared.4. Summary4.1 Microbes may be introduced into fuels as products coolin refinery tanks. Bacteria and fungi are carried along with d
48、ustparticles and water droplets through tank vents. In seawaterballasted tanks, microbes are transported with the ballast.D6469043Vessel compartments ballasted with fresh, brackish, or seawa-ter, all of which may contain substantial numbers of microbes,may easily become contaminated with the microbe
49、s trans-ported with the ballast water. See Section 6 for more a detaileddiscussion.4.2 After arriving in fuel tanks, microbes may either stick tooverhead surfaces or settle through the product. Some mi-crobes will adhere to tank walls, whereas others will settle tothe fuel/water interface. Most growth and activity takes placewhere fuel and water meet. The tank bottom fuel/waterinterface is the most obvious fuel/water boundary. However,there is also a considerable area of fuel/water interface on theinterior surface of tank-shells. Micro
