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5.1 This practice determines the effectiveness of UVGI devices for reducing viable microorganisms deposited on carriers.5.2 This practice evaluates the effect soiling agents have on UVGI antimicrobial effectiveness.5.3 This practice determines the delivered UVGI dose.1.1 This practice will define test conditions to evaluate ultraviolet germicidal irradiation (UVGI) light devices (mercury vapor bulbs, light-emitting diodes, or xenon arc lamps) that are designed to kill/inactivate microorganisms deposited on inanimate carriers.1.2 This practice defines the terminology and methodology associated with the ultraviolet (UV) spectrum and evaluating UVGI dose.1.3 This practice defines the testing considerations that can reduce UVGI surface kill effectiveness, that is, presence of a soiling agent.1.4 This practice does not address shadowing.1.5 This practice should only be used by those trained in microbiology and in accordance with the guidance provided by Biosafety in Microbiological and Biomedical Laboratories (5th edition), 2009, HHS Publication No. (CDC) 21-1112.1.6 This practice does not recommend either specific test microbes or growth media. Users of this practice shall select appropriate test microbes and growth media based on the specific objectives of their UV antimicrobial performance evaluation test plan.1.7 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.8 Warning—Mercury has been designated by many regulatory agencies as a hazardous substance that can cause serious medical issues. Mercury, or its vapor, has been demonstrated to be hazardous to health and corrosive to materials. Caution should be taken when handling mercury and mercury-containing products. See the applicable product Safety Data Sheet (SDS) for additional information. Users should be aware that selling mercury or mercury-containing products, or both, may be prohibited by local or national law.1.9 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.10 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 The principal purpose of irradiation is to help ensure the safety of these foods for human consumption. Irradiation significantly reduces the numbers of pathogenic bacteria such as Campylobacter, Shiga toxin-Producing E coli, Listeria monocytogenes, Salmonella, Staphylococcus aureus, and Yersinia enterocolitica.NOTE 3: Ionizing radiation doses below 10 kGy will reduce but may not eliminate spores of pathogenic bacteria including those of Clostridium botulinum, Clostridium perfringens, and Bacillus cereus.4.2 The process also inactivates parasites such as Trichinella spiralis and Toxoplasma gondii.4.3 The process may extend the shelf life of fresh meat and poultry by reducing the numbers of viable, spoilage bacteria, such as Pseudomonas species and lactic acid bacilli.4.4 Radiation processing of fresh, frozen, or processed meat and poultry is a critical control point (CCP) of a Hazard Analysis of Critical Control Points (HACCP) program. It serves as an important measure to control any residual risk from pathogenic microorganisms before the product reaches the consumer (4).4.5 The “Recommended International Code of Practice for Radiation Processing of Food” (CAC/RCP 19-1979) of the Codex Alimentarius identifies the essential practices to be implemented to achieve effective radiation processing of food, in general, in a manner that maintains quality and yields food products that are safe and suitable for consumption.1.1 This guide outlines procedures for the irradiation of fresh, frozen, or processed meat and poultry.NOTE 1: The Codex Alimentarius Commission defines meat as “the edible part of any mammal” and poultry as “any domesticated bird, including chicken, turkeys, ducks, geese, guinea-fowls, or pigeons” (CAC/MISC 5).NOTE 2: Current U.S. regulations limit the definition of meat and poultry as listed in 9 CFR Section 301.2 and 381.1, respectively. (2, 3).1.2 This guide covers the use of ionizing radiation to eliminate or reduce the numbers of vegetative, pathogenic microorganisms and parasites, and to extend the refrigerated shelf-life of those products by reducing the numbers of spoilage microorganisms in fresh, frozen, or processed meat and poultry. The absorbed dose for this application is typically less than 10 kGy.1.2.1 This guide covers gamma, electron beam, and X-radiation treatment.1.3 This guide addresses irradiation of pre-packaged product for retail sale or for use as an ingredient in other products. It also addresses the in-line irradiation of unpackaged product. Other specific ISO and ASTM standards exist for the irradiation of food. In those areas covered by ISO 14470, that standard takes precedence.1.4 This document is one of a set of standards that provides recommendations for properly implementing and utilizing radiation processing. It is intended to be read in conjunction with ISO/ASTM 52628.1.5 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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1.1 This test method describes the procedures required to carry out a pure-culture study for evaluating the biodegradation of degradable plastics in submerged culture under aerobic conditions. Degradation will be evaluated by weight loss, tensile strength loss, percent-elongation loss and changes in molecular-weight distribution. 1.2 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.

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4.1 Absorbed doses of or below 1 kGy can inactivate some parasites, such as the broad fish tapeworm (Dibothrocephalus latus) (2).4.2 Absorbed doses below 10 kGy can reduce or eliminate vegetative cells of pathogenic sporeforming and non-sporeforming microorganisms, such as Clostridium spp., Vibrio spp., Salmonellae, Listeria monocytogenes, or Staphylococcus aureus, that may be present in fresh or frozen product.4.2.1 Absorbed doses below 10 kGy can reduce the numbers of some spores, but are not adequate to reduce the potential health risk from microbial spores or toxins (3).4.3 Absorbed doses below 10 kGy can reduce or eliminate the vegetative cells of sporeforming and non-sporeforming microorganisms, such as Bacillus or Pseudomonas species, that cause spoilage of fresh product, thus extending refrigerated shelf life in many cases (4).1.1 This guide outlines procedures and operations for the irradiation of raw, untreated, fresh (chilled), or frozen finfish and aquatic invertebrates, while ensuring that the irradiated product is safe and wholesome.1.1.1 Aquatic invertebrates include mollusks, crustacea, echinoderms, etc.1.1.1.1 Mollusks include bivalve shellfish, such as clams, mussels, and oysters; snails; and cephalopods, such as squid and octopus.1.1.1.2 Crustacea include shellfish such as shrimp, lobster, crabs, prawns and crayfish.1.1.1.3 Echinoderms include sea urchins and sea cucumbers.1.2 This guide covers absorbed doses used to reduce the microbial and parasite populations in aquatic invertebrates and finfish. Such doses typically are below 10 kGy (1).21.2.1 This guide covers gamma, electron beam, and X-radiation treatment.1.3 The use of reduced-oxygen packaging (vacuum or modified atmosphere, and including products packed in oil) with irradiated, raw product is not covered by this guide. The anaerobic environment created by reduced-oxygen packaging provides the potential for outgrowth of, and toxin production from, Clostridium botulinum spores.1.4 This guide does not cover the irradiation of smoked or dried fish to reduce microbial load or to control insect infestation.1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.6 This document is one of a set of standards that provides recommendations for properly implementing and utilizing radiation processing. It is intended to be read in conjunction with ISO/ASTM Practice 52628.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 Spoilage of paint in the container can result in putrefaction, lowered pH, gas formation, and decrease in viscosity. This test method provides a standard procedure for the evaluation of the resistance of emulsion paints to microbial deterioration. The results should enable: (1) the paint manufacturer to select an effective preservative and (2) the supplier of preservatives to evaluate the performance in emulsion paints of competitive and developmental preservatives.4.2 This test method should be used preferably by persons who have had basic microbiological training.NOTE 1: The reliability of the results obtained from this test method is extremely dependent on the techniques employed. Improper techniques can result in a sterile sample appearing to be contaminated, and even worse, a contaminated sample appearing to be sterile (see also Note 2). It is recommended that you consult with your biocide supplier, raw material supplier, or an independent testing laboratory to confirm questionable results. Formulation and raw materials’ quality may also vary and thereby affect the test results.1.1 This test method covers the determination of the relative resistance of emulsion paints to attack in the container by microorganisms.1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 The technology to engineer industrial microorganisms (IMs) is evolving rapidly and the public, regulatory bodies, and industrial sectors require new tools to help evaluate the products of biotechnology (1)3. In particular, there is a need to clarify the nature and intent of genetic alterations present in many industrial microbial strains (2, 3).4.2 Currently, there is no systematic classification system to help differentiate among the many subtypes of engineered industrial microorganisms (4, 5). In response, a classification system for industrial microorganisms has been developed with the intent of facilitating the commercial use and development of industrial microorganisms and the biotechnology sector in general.4.3 This classification will be applied to all microorganisms for which there is an intended use, broadly referred to as “industrial microorganisms.” This classification covers both viable and non-viable microorganisms, in addition to any product that contains microbial DNA.4.4 This classification is not intended to apply to downstream products of industrial microorganisms that do not contain microbial DNA, for example, highly purified proteins or small molecules produced by industrial microorganisms.1.1 This classification applies to all industrial microorganisms, both classically derived and those produced through genetic engineering methods.1.2 The scope of this classification does not include plants and animals. This classification would not be applied to any downstream products derived from industrial microorganisms unless they contain microbial deoxyribonucleic acid (DNA).1.3 This classification includes fields for genotype class, biosafety, mode/intent of use, and the extent of DNA sequence information for a given industrial microbial strain.1.4 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 Bacteria and fungi present in municipal solid wastes (as well as in other forms of waste) may become airborne as dusts during waste processing. Several investigations to determine the health significance of these microbiological aerosols have been hindered by the lack of standardized procedures for sampling airborne bacteria and fungi in an industrial environment and by the absence of standards for assessing their health significance. Because it is difficult to correlate airborne levels of bacteria and fungi with epidemiological data, this standard is designed to permit the formation of a data base to aid in the assessment of the health significance of airborne microorganisms. It is intended that the use of this practice will improve sampling precision and thereby facilitate comparisons between sampling results.1.1 This practice covers sampling of airborne microorganisms at municipal solid-waste processing facilities, hereafter referred to as facilities. Investigators should consult Practice D1357 for the general principles of conducting an air-sampling program.1.2 This practice applies only to sampling airborne bacteria and fungi, not viruses. Since sampling airborne viruses is significantly more difficult than sampling bacteria and fungi, reliable methods of sampling viruses are not yet available.

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5.1 The procedure can be incorporated into protocols used to evaluate test materials containing antibacterial ingredients that are intended to reduce significantly the number of organisms on intact skin. It also may be used to provide an indication of residual antibacterial activity (as in Guide E2752). Examples of test materials, for which this practice is applicable, include pre-operative skin preparations, hand-washes, surgical scrubs, acne reduction products, and others. For each type of test material, types of resident flora or surrogate organisms, or a combination thereof, may differ and should be considered (this is, aerobic bacteria, anaerobic bacteria, yeast, or mold).5.2 The procedure may be used in protocols intended to evaluate and identify resident flora from the skin.5.3 Performance of this technique may require the knowledge of regulations pertaining to the protection of human subjects if the protocol involves application of the technique to the skin of human subjects.1.1 This practice is designed to recover microorganisms from the skin of human subjects or human subject surrogates (animal skin, isolated porcine skin, human skin equivalents, and other such surfaces).1.2 Knowledge of microbiological techniques is required for these procedures.1.3 It is the responsibility of the investigator to determine if Good Laboratory Practice (GLP) and Good Clinical Practice (GCP) is required.1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 This test method measures the concentration of ATP present in the sample. ATP is a constituent of all living cells including bacteria and fungi. Consequently, the presence of ATP is a reliable indicator of microbial contamination in fuel systems. ATP is not associated with matter of non-biological origin.5.2 This test method differs from Test Method D4012 as follows:5.2.1 By providing for the rapid determination of ATP present in a fuel (petroleum) sample, a fuel and water mixture sample, fuel-associated bottom water sample, and extracellular ATP freely available in the fuel or aqueous sample matrix;5.2.2 By providing for a method to capture, extract, and quantify ATP using self-contained test device and luminometer;5.2.3 By providing a method of quantifying ATP present in fuel or water matrices in generally less than 10 min; and5.2.4 By providing for the rapid separation of the ATP from chemical interferences that have previously prevented the use of ATP determinations in complex fluids containing hydrocarbons and other organic molecules.5.3 This test method does not require the use of hazardous materials and does not generate biohazard waste.5.4 This test method can be used to estimate viable microbial biomass, to evaluate the efficacy of antimicrobial pesticides, and to monitor microbial contamination in fuel storage and distribution systems.1.1 This test method provides a protocol for capturing, concentrating, and testing the adenosine triphosphate (ATP) present in a fuel system sub-sample (that is, test specimen) associated with:1.1.1 Microorganisms and hydrophilic particles found in liquid fuels as described in Table X6.1, or1.1.2 Microorganisms and hydrophilic particles found in mixture of fuel and associated bottom water or just associated bottom water.1.1.3 ATP detected by this bioluminescence test can be derived from cellular ATP, extra-cellular ATP, or some combination of both.1.1.4 Cellular and extra-cellular ATP utilized to perform ATP bioluminescence are captured and concentrated from a fuel system sample into an aqueous test specimen (that is, sub-sample) for testing. For example, for a fuel system sample that does not contain any visible fuel associated bottom water, the aqueous test specimen is the capture solution itself described in 8.2.1.1. For fuel system samples that are a mixture of fuel and associated bottom water (that is, free water), the test specimen is an aliquant of the capture solution and associated bottom water.1.2 The ATP is measured using a patented bioluminescence enzyme assay, whereby light is generated in amounts proportional to the concentration of ATP in the sample. The light is produced and measured quantitatively using dedicated ATP test pens2 and a dedicated luminometer2 and reported in (instrument specific) Relative Light Units.1.3 This test method is equally suitable for use in the laboratory or field.1.4 Although bioluminescence is a reliable and proven technology, this method does not differentiate ATP from bacteria or fungi.1.5 For water or capture solution samples, the concentration range of ATP detectable by this test method is 1 × 10–11 M to 3 × 10–8 M which is equivalent to 1 × 10–14 moles/mL to 3 × 10–11 moles/mL for water samples or capture solution. Assuming testing on fuel phase is performed on a 500 mL volume of fuel the equivalent concentrations is fuel would be: 6 × 10–11 M to 2 × 10–14 M.1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.6.1 There is one exception—Relative Light Unit (RLU) as defined in 3.1.19.1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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5.1 The different procedures and methods are designed to be used to produce survival data after microorganisms are exposed to antimicrobial agents in order to calculate values that can be used to analyze and rationalize the effectiveness of antimicrobial agents when tested using other, often applied test methods.5.2 The data from these test procedures may be used in the selection and design of other tests of effectiveness of antimicrobial agents, some of which may be required by regulatory agencies to establish specific claims. Basic kinetic information about killing rate often serves as the initial information on which a testing program can be built.1.1 This guide covers the methods for determining the death rate kinetics expressed as D-values. These values can be derived from the construction of a kill curve (or survivor curve) or by using other procedures for determining the number of survivors after exposure to antimicrobial chemicals or formulations. Options for calculations will be presented as well as the method for calculation of a concentration coefficient.1.1.1 The test methods are designed to evaluate antimicrobial agents in formulations to define a survivor curve and to subsequently calculate a D-value. The tests are designed to produce data and calculate values that provide basic information of the rate-of-kill of antimicrobial formulations tested against single, selected microorganisms. In addition, calculated D-values from survivor curves from exposure at different dilutions of antimicrobial can be used to show the effect of dilution by calculation of the concentration exponent, η (2). D-value determination assumes the ideal of first-order killing reactions that are reflected in a straight-line reduction in count where a count-versus-time plot is done. The goal here is not to determine the time at which no survivors are found, but to determine a standard value that can be used in processing and exposure determinations or used to estimate dilutions.1.1.2 As an example of potential use of kill curve data, the published FDA, OTC Tentative Final Monograph for Health-Care Antiseptic Drug Products, Proposed Rule, June 17, 1994 has suggested the testing of topically applied antimicrobial products using survival curve (or kill curve) calculations. The methods described in this guide are applicable to these products, but adjustments such as the use of antifoaming agents when the reaction mixture is stirred may be necessary to counteract the presence of detergents in many formulations. Frequently the sampling for these tests is done after very short intervals of exposure to the formulation, such as 30 and 60 s. This methodology also has been applied to preservative testing of antimicrobial ingredients in more complex cosmetic formulations (5).1.2 The test methods discussed should be performed only by those trained in microbiological techniques.1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 The principal purpose of irradiation is to reduce the number of pathogenic bacteria, such as Campylobacter, Escherichia coli 0157:H7, Listeria monocytogenes, Staphylococcus aureus or Salmonella spp., in processed meats and poultry to make these foods safer for human consumption.Note 3—Ionizing radiation doses below 10 kGy will reduce but not eliminate spores of pathogenic bacteria including those of Clostridium botulinum, Clostridium perfringens and Bacillus cereus.4.2 Irradiation treatment can extend the shelf life of processed meats and poultry by reducing the numbers of vegetative spoilage bacteria, such as Pseudomonas species and lactic acid bacilli.4.3 Irradiation treatment also inactivates parasites such as Trichinella spiralis and Toxoplasma gondii.4.4 Radiation processing of the final product in its packaging is a critical control point (CCP) of a Hazard Analysis of Critical Control Points (HACCP) concept for the production of Processed Meat and Poultry. It serves as an important measure to control any residual risk from pathogen microorganisms just before the product reaches the consumer.4.5 The “Recommended International Code of Practice for Radiation-processing of Food” (CAC/RCP 19-1979) of the Codex Alimentarius identifies the essential practices to be implemented to achieve effective radiation processing of food, in general, in a manner that maintains quality and yields food products that are safe and suitable for consumption.1.1 This guide outlines procedures for the irradiation of pre-packaged refrigerated and frozen processed meat and poultry products.Note 1—The Codex Alimentarius Commission defines “meat” (including poultry and game) as “the edible part of any mammal slaughtered in an abattoir,” and “poultry meat” as “the edible part of slaughtered domesticated birds, including chicken, turkeys, ducks, geese, guinea-fowls, or pigeons.” (CAC/RCP 13-1976)Note 2—Current U.S. regulations limit the definition of livestock species to cattle, sheep, swine, goat, horse, mule, or other equine and poultry species to chicken, turkey, duck, goose, and guinea (2, 3).1.2 This guide addresses all refrigerated and frozen meat and poultry products NOT covered by Guide F1356.1.3 This guide provides information regarding absorbed doses used for inactivation of parasites and reduction of bacterial load. Such doses are typically less than 10 kilogray (kGy).

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5.1 A rapid and routine procedure for determining biomass of the living microorganisms in cultures, waters, wastewaters, and in plankton and periphyton samples taken from surface waters is frequently of vital importance. However, classical techniques such as direct microscope counts, turbidity, organic chemical analyses, cell tagging, and plate counts are expensive, time-consuming, or tend to underestimate total numbers. In addition, some of these methods do not distinguish between living and nonliving cells.5.2 This test method measures the concentration of cellular-ATP present in the sample. ATP is a constituent of all living cells, including bacteria, algae, protozoa, and fungi. Consequently, the presence of cellular-ATP is an indicator of total metabolically active microbial contamination in water. ATP is not associated with matter of non-biological origin.5.3 The ATP (luciferin-luciferase) method is a rapid, sensitive determination of viable microbial biomass. ATP is the primary energy donor for life processes, does not exist in association with nonliving detrital material, and the amount of ATP per unit of biomass (expressed in weight) is relatively constant. (ATP per cell varies with species and physiological state of the organism.)5.4 This test method can be used to:5.4.1 Estimate viable microbial biomass in cultures and waters.5.4.2 Estimate the amount of total viable biomass in plankton and periphyton samples.5.4.3 Estimate the number of viable cells in a unispecies culture if the cATP content (or if the average amount of cATP) per cell is known.5.4.4 Estimate and differentiate between zooplanktonic, phytoplanktonic, bacterial, and fungal cATP through size fractionation of water samples.5.4.5 Measure the mortality rate of microorganisms in toxicity tests in entrainment studies, and in other situations where populations or assemblages of microorganisms are placed under stress.5.5 This test method is similar to Test Methods D7687 and E2694 except for the volumes sampled, and omission of wash and drying steps used in Test Methods D7687 and E2694 to remove interferences (1.3).5.6 Although ATP data generally covary with culture data in water samples, different factors affect cATP concentration than those that affect culturability.5.6.1 Culturability is affected primarily by the ability of captured microbes to proliferate on the growth medium provided, under specific growth conditions. Consequently, a proportion of the active or inactive microbial population present in a sample may be viable but not detected by any one culture test.35.6.2 ATP concentration is affected by: the microbial species present, the physiological states of those species, and the total bioburden (see Appendix X1).5.6.2.1 One example of the species effect is that the amount of ATP per cell is substantially greater for active fungal cells than bacteria (Appendix X1).5.6.2.2 Within a species, cells that are more metabolically active will have more ATP per cell than dormant cells, such as fungal spores.5.6.2.3 The greater the total bioburden, the greater the ATP concentration in a sample.1.1 This test method covers a protocol for capturing, extracting and quantifying the cellular adenosine triphosphate (cATP) content associated with microorganisms normally found in laboratory cultures and waters in plankton and periphyton samples from waters.1.2 The ATP is measured using a bioluminescence enzyme assay, whereby light is generated in amounts proportional to the concentration of ATP in the samples. The light is produced and measured quantitatively as relative light units (RLU) which are converted by comparison with an ATP standard and computation to pg ATP/mL.1.3 This method does not remove all known chemical interferences, known to either luminesce in the 530 nm ± 20 nm range, or to quench light emitted in that range. It should not be used to determine ATP concentrations in samples with dissolved organic compounds, heavy metals or >10 000 ppm total dissolved solids. Alternative methods have been developed for determining ATP concentrations in fluids samples likely to contain such interferences (Test Methods D7687 and E2694).1.4 Knowledge of the concentration of ATP can be related to viable biomass or metabolic activity of microorganisms (Appendix X1).1.5 This test method offers a high degree of sensitivity, rapidity, accuracy, and reproducibility.1.6 The analyst should be aware that the precision statement pertains only to determinations in reagent water and not necessarily in the matrix being tested.1.7 This test method is equally suitable for use in the laboratory or field.1.8 The method normally detects cATP concentrations in the range of 0.1 pg cATP/mL (–1.0Log10 [pg cATP/mL]) to4 000 000 pg cATP/mL (6.6 Log10 [pg cATP/mL]) in 50 mL water samples.1.9 Providing interferences can be overcome, bioluminescence is a reliable and proven method for qualifying and quantifying ATP, although the method does not differentiate between ATP from different sources, for example, from different types of microorganisms, such as bacteria, fungi, algae and protozoa.1.10 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.11 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.12 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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4.1 The purpose of irradiation of dried spices, herbs, and vegetable seasonings is to control pathogenic bacteria, molds, and yeasts present in these commodities (2-7).4.2 The process will also kill any insects present, at all stages of development.NOTE 2: CAC/RCP 19-1979 of the Codex Alimentarius identifies the essential practices to be implemented to achieve effective radiation processing of food, in general, in a manner that maintains quality and yields food commodities that are safe and suitable for consumption.1.1 This guide covers procedures for irradiation of dried spices, herbs, and vegetable seasonings for microbiological control. Generally, these items have moisture content of 4.5 to 12 % and are available in whole, ground, chopped, or other finely divided forms, or as blends. The blends may contain sodium chloride and minor amounts of dry food materials ordinarily used in such blends.1.2 This guide covers gamma, electron beam, and X-radiation treatment. This guide also covers low energy electron beam treatment where only part of the product is irradiated (that is, surface treatment).1.3 This guide covers absorbed doses ranging from 3 to 30 kilogray (kGy).NOTE 1: U.S. regulations permit a maximum dose of 30 kGy. (See 21CFR 179.26.) EU regulations permit a maximum dose of 10 kGy. (See Directive 1999/3/EC.)1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.5 This document is one of a set of standards that provides recommendations for properly implementing and utilizing radiation processing. It is intended to be read in conjunction with Practice ISO/ASTM 52628.1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

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