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AS 2054-1977 Spirit levels for use in precision engineering 被代替 发布日期 :  1977-09-01 实施日期 : 

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ASTM D6734-01(2009) Standard Test Method for Low Levels of Coliphages in Water (Withdrawn 2015) Withdrawn, No replacement 发布日期 :  1970-01-01 实施日期 : 

Coliphage organisms may serve as indicators of fecal contamination. The presence of coliphages in water in the absence of a disinfectant indicates the probable presence of fecal contamination. The absolute relationship between the number of coliforms and coliphages in natural waters has not been conclusively demonstrated. Coliphages are generally more resistant than coliforms to chlorination and may have some advantage over coliforms as an indicator of treatment efficiency in disinfected waters. The detection of coliphages in a water sample depends upon the use of a sensitive host strain in the coliphage assay. Coliphages may be detected by this concentration procedure in 6.5 h to provide important same-day information on the sanitary quality of water. The lower detection limit of this concentration procedure is 1 coliphage per volume of water sample tested.1.1 This test method covers the determination of coliphages infective for E. coli C in water. The test method is simple, inexpensive, and yields an indication of water quality within 6.5 h. This coliphage method can determine coliphages in water down to 1 coliphage per volume of water sampled.1.2 The test method is applicable to natural fresh water samples and to settled, filtered or finished water samples.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 and health practices and determine the applicability of regulatory limitations prior to use.

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5.1 The purpose of this guide is to furnish qualified technical personnel with pertinent information for the selection of cleaning methods for cleaning materials and equipment to be used in oxygen-enriched environments. This guide furnishes qualified technical personnel with guidance in the specification of oxygen system cleanliness needs. It does not actually specify cleanliness levels.5.2 Insufficient cleanliness of components used in oxygen systems can result in the ignition of contaminants or components by a variety of mechanisms such as particle, mechanical, or pneumatic impact. These mechanisms are explained in detail in Guide G88.5.3 Adequate contamination control in oxygen systems is imperative to minimize hazards and component failures that can result from contamination. Contamination must also be minimized to ensure an acceptable product purity.5.4 Removal of contaminants from materials and components depends on system configuration, materials of construction, and type and quantity of contaminant.5.5 Examples of cleaning procedures contained herein may be followed or specified for those materials, components, and equipment indicated. The general cleaning text can be used to establish cleaning procedures for materials, components, equipment, and applications not addressed in detail. See Guide G127 for discussion of cleaning agent and procedure selection.1.1 This guide covers the selection of methods and apparatus for cleaning materials and equipment intended for service in oxygen-enriched environments. Contamination problems encountered in the use of enriched air, mixtures of oxygen with other gases, or any other oxidizing gas may be solved by the same cleaning procedures applicable to most metallic and nonmetallic materials and equipment. Cleaning examples for some specific materials, components, and equipment, and the cleaning methods for particular applications, are given in the appendixes.1.2 This guide includes levels of cleanliness used for various applications and the methods used to obtain and verify these levels.1.3 This guide applies to chemical-, solvent-, and aqueous-based processes.1.4 This guide describes nonmandatory material for choosing the required levels of cleanliness for systems exposed to oxygen or oxygen-enriched atmospheres.1.5 This guide proposes a practical range of cleanliness levels that will satisfy most system needs, but it does not deal in quantitative detail with the many conditions that might demand greater cleanliness or that might allow greater contamination levels to exist. Furthermore, it does not propose specific ways to measure or monitor these levels from among the available methods.1.6 Units—The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.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. Federal, state, and local safety and disposal regulations concerning the particular hazardous materials, reagents, operations, and equipment being used should be reviewed by the user. The user is encouraged to obtain the Material Safety Data Sheet (MSDS) from the manufacturer for any material incorporated into a cleaning process. Specific cautions are given in Section 8.1.8 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 Although cabin air quality has been measured on numerous occasions and in many studies, there is very little guidance available for interpreting such data. Guidance for identifying contaminants and associated exposure levels that would cause concern in aircraft cabins is very limited. Federal Aviation Administration (FAA) Airworthiness Standards (14 CFR 25) provide regulatory guidance that explicitly applies to the aircraft cabin environment. The FAA standards, however, define acceptable exposure limits for a limited number of chemical contaminants (ozone, carbon dioxide, and carbon monoxide). Another limitation of the FAA standards is that these are design standards only and are not operational standards; thus, once an aircraft is put in service these standards are not strictly applicable.5.2 Measurements of aircraft cabin air quality often lead to a much larger list of volatile and semi-volatile organic chemicals of potential concern. Exposures to these chemicals, however, are largely unregulated outside of the industrial workplace.5.3 An important feature of the aircraft cabin environment is that both passengers (public) and flight attendants (worker population) occupy it simultaneously. Therefore, workplace exposure guidelines cannot simply be extended to address exposures in aircraft cabin environment. Also, the length of flights and work shifts can vary considerably for flight attendants.5.4 Contaminant levels of concern for the general public must account for the non-homogeneity of the population (for example, address sensitive individuals, the differences between passenger and crew activity levels, location, health status, personal microenvironment). Levels of concern associated with industrial workplace exposures typically consider a population of healthy adults exposed for 40 h per week (1).4 Consequently, exposure criteria developed to protect public health typically are more stringent than those for workers.5.4.1 Given that the aircraft cabin environment must meet the needs of passengers as well as crew, a more stringent concentration level based upon the general population would protect both.5.4.2 Aircraft cabin air quality must be addressed both during flight and on the ground because the conditions during flight are much different than when the aircraft is on the ground.1.1 This guide provides methodology to assist in interpreting results of air quality measurements conducted in aircraft cabins. In particular, the guide describes methodology for deriving acceptable concentrations for airborne chemical contaminants, based on health and comfort considerations.1.2 The procedures for deriving acceptable concentrations are based on considerations of comfort and health effects, including odor and irritant effects, of individual chemical contaminants being evaluated. The guide does not provide specific benchmark or guidance values for individual chemicals to compare with results of air quality measurements.1.3 Chemical contaminant exposures under both routine and episodic conditions for passengers and crew are considered.1.4 This guide does not address airborne microbiological contaminants, which are also important in consideration of aircraft cabin air quality. This guide also does not address methodologies for investigations of air quality complaints.1.5 This guide assumes that a list of chemical contaminants of potential concern has been developed based on existing concentration, emission, or material composition data.1.6 The primary information resources for developing acceptable concentrations are databases and documents maintained or published by cognizant authorities or organizations concerned with health effects of exposure to contaminants.1.7 Acceptable concentrations developed through this guide may be used as a basis for selecting test methods with adequate reliability and sensitivity to assess the acceptability of aircraft cabin environments.1.8 Procedures described in this guide should be carried out in consultation with qualified toxicologists and health effects specialists to ensure that acceptable concentrations developed are consistent with the current scientific understanding and knowledge base.1.9 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.10 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.1.11 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 This test method usually requires several minutes per sample. Other test methods which can be used for the determination of phosphorus in lubricating oils include WDXRF Test Method D4927 and ICPAES Test Methods D4951 and D5185. However, this test method provides more precise results than Test Methods D4951 or D5185.4.2 Lubricating oils are typically blends of additive packages, and their specifications are also determined, in part, by elemental composition. This test method can be used to determine if unused lubricating oils meet specifications with respect to elemental composition.4.3 It is expected that GF 4 grade engine oils marketed in the years 2004 to 2005 will have a maximum phosphorus concentration level of 500 mg/kg to 800 mg/kg. These limits are required to minimize poisoning of automotive emission control catalysts by volatile phosphorus species. It is anticipated that the later grades of oils may have even lower phosphorus levels.1.1 This test method covers the quantitative determination of phosphorus in unused lubricating oils, such as International Lubricant Standardization and Approval Committee (ILSAC) GF 4 and similar grade engine oils, by inductively coupled plasma atomic emission spectrometry.1.2 The precision statements are valid for dilutions in which the mass % sample in solvent is held constant in the range of 1 % to 5 % by mass oil.1.3 The precision tables define the concentration ranges covered in the interlaboratory study (500 mg/kg to 800 mg/kg). However, both lower and higher concentrations can be determined by this test method. The low concentration limits are dependent on the sensitivity of the ICP instrument and the dilution factor. The high concentration limits are determined by the product of the maximum concentration defined by the linear calibration curve and the sample dilution factor.1.4 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.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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4.1 Trace amounts of water may be detrimental to the use of chlorine in some applications. The amount of water in the chlorine must be known to prevent problems during its use.1.1 This test method covers the determination of the content of water in liquid chlorine in the concentration range of 0.5 to 15 mg/kg (ppm).1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses are for information only.1.3 Review the current Safety Data Sheets (SDS) for detailed information concerning toxicity, first aid procedures, and safety precautions.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 and health practices and determine the applicability of regulatory limitations prior to use. See Section 7 for specific hazards statements.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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