5.1 This procedure is designed to determine the effectiveness of antimicrobial agents intended for microbial control in invert emulsions and other water containing hydraulic fluids.1.1 This laboratory practice is designed to evaluate the utility and effectiveness of antimicrobial agents intended to control microbial growth in invert emulsions and other water containing hydraulic fluids.NOTE 1: Procedures for preparation of water soluble hydraulic fluids and recovery of organisms appear in Practice E2169.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.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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3.1 Persons engaged in forensic investigations are responsible for identifying significant data. They then analyze and correlate the data and report conclusions and opinions. These opinions should be supported by the data, reported in a form that is understandable to a layman familiar with the incident, and capable of being evaluated by knowledgeable scientists, engineers, or investigators.3.2 This practice is intended to serve as a guideline for the scientific or technical expert in conducting an investigation, which includes analyzing and evaluating facts. In addition, this practice may assist others in understanding and evaluating the work performed. Refer to Practice E1188 for guidance pertaining to the actual collection of information and physical evidence, and Practice E1020 for guidance regarding the initial reporting of the incident.1.1 This practice establishes criteria for evaluating scientific and technical data, and other relevant considerations, which constitute acceptable bases for forming scientific or technical expert opinions.1.2 This practice recommends generally acceptable professional practice, although the facts and issues of each situation require specific consideration, and may involve matters not expressly dealt with herein. Deviations from this practice are not necessarily wrong or inferior, but should be documented and justifiable, if compliance with this standard is claimed. Not all aspects of this practice may be applicable in all circumstances.1.3 This practice offers a set of instructions for performing one or more specific operations. This document cannot replace education or experience and should be used in conjunction with professional judgment. Not all aspects of this practice may be applicable in all circumstances.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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4.1 The test results provide an indication of the motor life of an electric motorized nozzle. The end of motor life will be judged in accordance with Section 3.1.1 This test method covers the motorized nozzle used in household or commercial central vacuum cleaning systems.1.2 This test method provides a test for determining operating motor life in hours by an accelerated laboratory procedure. The motors are tested while mounted and operated in the motorized nozzle.1.3 This test method covers only the motorized nozzle. The system used to provide the airflow source is not under consideration.1.4 This test method is limited to the determination of motor life for an electrically powered household or commercial motorized nozzle.1.5 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are for information only.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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5.1 This test method is used to evaluate automotive engine oils for protection of engines against bearing weight loss.5.2 This test method is also used to evaluate the SIG capabilities of multiviscosity-graded oils.5.3 Correlation of test results with those obtained in automotive service has not been established.5.4 Use—The Sequence VIII test method is useful for engine oil specification acceptance. It is used in specifications and classifications of engine lubricating oils, such as the following:5.4.1 Specification D4485.5.4.2 API Publication 1509 Engine Oil Licensing and Certification System.65.4.3 SAE Classification J304.1.1 This test method covers the evaluation of automotive engine oils (SAE grades 0W, 5W, 10W, 20, 30, 40, and 50, and multi-viscosity grades) intended for use in spark-ignition gasoline engines. The test procedure is conducted using a carbureted, spark-ignition Cooperative Lubrication Research (CLR) Oil Test Engine (also referred to as the Sequence VIII test engine in this test method) run on unleaded fuel. An oil is evaluated for its ability to protect the engine and the oil from deterioration under high-temperature and severe service conditions. The test method can also be used to evaluate the viscosity stability of multi-viscosity-graded oils. Companion test methods used to evaluate engine oil performance for specification requirements are discussed in the latest revision of Specification D4485.1.2 Correlation of test results with those obtained in automotive service has not been established. Furthermore, the results obtained in this test are not necessarily indicative of results that will be obtained in a full-scale automotive spark-ignition or compression-ignition engine, or in an engine operated under conditions different from those of the test. The test can be used to compare one oil with another.1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3.1 Exceptions—The values stated in inch-pounds for certain tube measurements, screw thread specifications, and sole source supply equipment are to be regarded as standard.1.3.1.1 The bearing wear in the text is measured in grams and described as weight loss, a non-SI term.1.4 This test method is arranged as follows:Subject SectionIntroduction   1Referenced Documents 2Terminology 3Summary of Test Method 4  Before Test Starts 4.1  Power Section Installation 4.2  Engine Operation (Break-in) 4.3  Engine Operation (Test/Samples) 4.4  Stripped Viscosity 4.5  Test Completion (BWL) 4.6 5  Evaluation of Automotive oils 5.1  Stay in Grade Capabilities 5.2  Correlation of Results 5.3  Use 5.4Apparatus 6  Test Engineering, Inc. 6.1  Fabricated or Specially Prepared Items 6.2  Instruments and Controls 6.3  Procurement of Parts 6.4Reagents and Materials 7  Reagents 7.1  Cleaning Materials 7.2  Expendable Power Section-Related Items 7.3  Power Section Coolant 7.4  Reference Oils 7.5  Test Fuel 7.6Test Oil Sample Requirements 8  Selection 8.1  Inspection 8.2  Quantity 8.3Preparation of Apparatus 9  Test Stand Preparation 9.1  Conditioning Test Run on Power Section 9.2  General Power Section Rebuild Instructions 9.3  Reconditioning of Power Section After Each Test 9.4Calibration 10  Power Section and Test Stand Calibration 10.1  Instrumentation Calibration 10.2  Calibration of AFR Measurement Equipment 10.3  Calibration of Torque Wrenches 10.4Engine Operating Procedure 11  Run-In and Flush 11.1  Test Operating Conditions 11.2  Air-Fuel Ratio and Spark Advance 11.3  Air, Off-Gas and Blowby Measurement 11.4  Unscheduled Shutdowns 11.5  Oil Sampling and Oil Addition 11.6  Periodic Measurements 11.7  Final Oil Drain and Oil Consumption Computation 11.8  Operational Validity Criteria 11.9  Test Completion 11.10Determination of Test Results 12  Oil Analysis 12.1  Test Bearing Weight Loss Determination 12.2Report 13Precision and Bias 14  Precision 14.1  Bias 14.2Use of ASTM Rounding 15Keywords 16ANNEXESASTM Test Monitoring Center Organization Annex A1ASTM Test Monitoring Center: Calibration Procedures Annex A2ASTM Test Monitoring Center: Maintenance Activities Annex A3ASTM Test Monitoring Center: Related Information Annex A4Measurement of Connecting Rod Bearing Clearance andJournal Taper Annex A5Measurement of Main Bearing Clearance Annex A6Measurement of Piston-to-Sleeve Clearance Annex A7Control Chart Technique for a Laboratory's SeverityAdjustment (SA) Annex A8Recommended New Liner Honing Procedure Annex A9Sequence VIII Oil Priming Procedure Annex A10Alternative Crankcase Breather Configuration Annex A11Connecting Rod Bearing Cleaning Procedure Annex A12Electronic Ignition Conversion Annex A13System Response Procedure Annex A14Air-Fuel Ratio Measurement Annex A15Lead Decontamination Procedure Annex A16Crankshaft Rear Seal Conditioning Annex A17Report Forms and Data Dictionary Annex A18Stay-in-Grade Oil Analysis Procedure Annex A19APPENDIXESSuggested Method for Salvaging Camshaft Bearing Journals Appendix X1Data Log Sheets Appendix X21.5 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. Specific precautionary statements are provided throughout this test method.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 The significance and use of each test method will depend on the system in use and the purpose of the test method listed under Section 6. Use the most recent editions of the test methods.1.1 This guide covers information without specific limits, for selecting standard test methods for testing hydrocarbon-based quench oils for quality and aging.1.2 The values stated in SI units are to be regarded as standard.1.2.1 Exception—The units 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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5.1 This test method was developed to evaluate the liner scuffing and ring distress performance of engine oils in turbocharged and intercooled four-cycle diesel engines equipped with EGR, uncoated top rings, and running on ultra-low sulfur diesel fuel. Results are obtained from used oil analysis, operational data, and component measurements before and after test.5.2 The test method may be used for engine oil specification acceptance when all details of the procedure are followed.1.1 This test method covers an engine test procedure for evaluating diesel engine oils for performance characteristics, including adhesive wear between an uncoated piston ring and cylinder liner. This test method is commonly referred to as the DD13 Scuffing Test.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.2.1 Exception—Where there is no direct SI equivalent, such as the units for screw threads, National Pipe Threads/diameters, tubing size, and single source supply equipment specifications.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. See Annex A2 for specific safety precautions.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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1.1 This test method defines a procedure for evaluating the craze resistance of coated transparent plastics subjected to cyclic bending stresses induced by pressurizing the specimen under ambient, hot, and cold temperature conditions. 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. 1.3 The values stated in SI units are to be regarded as the standard.

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5.1 The compatibility of packaging materials with a medical device is a requirement of many regulatory bodies. Since most medical devices are used or implanted in, around, or on the human body, the benefits of these devices must outweigh the risks. Therefore, the packaging materials that come in contact with the medical device must also be evaluated and determined to be safe for use with the human body in that they have no negative impact on the physical, chemical, or biological properties of the device. This evaluation may include both a study of relevant experience with, and actual testing of, packaging materials. Such an evaluation may result in the conclusion that no testing is needed if the material has a demonstrable history of safe use in the specific role that is the same as that of the package under design.5.2 The medical device manufacturer determines the need for appropriate testing, with consideration of the device/package interactions, if any. When screening information is needed regarding the biocompatibility of the packaging, cytotoxicity testing from the supplier is typically performed.1.1 This guide provides information to determine the appropriate testing for biocompatibility of medical device packaging materials that have the potential to contact the patient directly or indirectly.1.2 This guide does not apply to secondary or tertiary packaging materials.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 testing and inspection of concrete and concrete aggregates are important elements in obtaining quality construction. A testing agency providing these services shall be selected with care.4.2 A testing agency shall be deemed qualified to perform and report the results of its tests if the agency meets the requirements of this practice. The testing agency services shall be provided under the technical direction of a registered professional engineer.4.3 This practice establishes essential characteristics pertaining to the organization, personnel, facilities, and quality systems of the testing agency. This practice may be supplemented by more specific criteria and requirements for particular projects.1.1 This practice identifies and defines the duties, responsibilities, and minimum technical requirements of testing agency personnel and the minimum technical requirements for equipment utilized in testing concrete and concrete aggregates for use in construction.1.2 This practice provides criteria for the evaluation of the capability of a testing agency to perform designated ASTM test methods on concrete and concrete aggregates. It can be used by an evaluation authority in the inspection or accreditation of a testing agency or by other parties to determine if the agency is qualified to conduct the specified tests.NOTE 1: Specification E329 provides criteria for the evaluation of agencies that perform the inspection of concrete during placement.1.3 This practice provides criteria for Inspection Bodies and Accreditation Bodies that provide services for evaluation of testing agencies in accordance with this practice.1.4 The text of this standard references notes and footnotes, which provide explanatory material and shall not be considered as requirements of 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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3.1 These tests are mainly intended for referee purposes but may also be used for quality control of rubber production. They may be used in research and development work for comparison of different rubber samples in a standard formula.3.2 These test methods may also be used to obtain values for customer acceptance of rubber.1.1 These test methods cover the standard materials, test formulas, mixing procedures, and test methods for the evaluation and production control of oil-extended polybutadiene rubber (OE-BR) polymerized in an appropriate solution.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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5.1 This test method was developed to evaluate automotive engine oils for protection against oil thickening and engine wear during moderately high-speed, high-temperature service.5.2 The increase in oil viscosity obtained in this test method indicates the tendency of an oil to thicken because of oxidation. In automotive service, such thickening can cause oil pump starvation and resultant catastrophic engine failures.5.3 The deposit ratings for an oil indicate the tendency for the formation of deposits throughout the engine, including those that can cause sticking of the piston rings in their grooves. This can be involved in the loss of compression pressures in the engine.5.4 The camshaft and lifter wear values obtained in this test method provide a measure of the anti-wear quality of an oil under conditions of high unit pressure mechanical contact.5.5 The test method was developed to correlate with oils of known good and poor protection against oil thickening and engine wear. Specially formulated oils that produce less than desirable results with unleaded fuels were also used during the development of this test method.5.6 The Sequence IIIF engine oil test has replaced the Sequence IIIE test and can be used in specifications and classifications of engine lubricating oils, such as:5.6.1 Specification D4485,5.6.2 Military Specification MIL-PRF-2104, and5.6.3 SAE Classification J183.1.1 This test method covers an engine test procedure for evaluating automotive engine oils for certain high-temperature performance characteristics, including oil thickening, varnish deposition, oil consumption, as well as engine wear. Such oils include both single viscosity grade and multiviscosity grade oils that are used in both spark-ignition, gasoline-fueled engines, as well as in diesel engines.NOTE 1: Companion test methods used to evaluate engine oil performance for specification requirements are discussed in SAE J304.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.2.1 Exceptions—The values stated in inches for ring gap measurements are to be regarded as standard, and where there is no direct SI equivalent such as screw threads, National Pipe Threads/diameters, tubing size, or single source supply equipment specifications.1.3 This test method is arranged as follows:Subject Section 1Referenced Documents 2Terminology 3Summary of Test Method 4 5Apparatus 6 Laboratory 6.1 Drawings 6.2 Specified Equipment 6.3 Test Engine 6.4  Engine Parts 6.4.1 Engine Speed and Torque Control 6.5 Sequence IIIF Fluid Conditioning Module 6.6  Engine Cooling System 6.6.1 Flushing Tank 6.7 Coolant Mixing Tank 6.8 Condenser Cooling Systems 6.9 Engine Oil-Cooling System 6.10 Fuel System 6.11 Induction Air Supply Humidity, Temperature, and Pressure 6.12 Temperature Measurement 6.13  Thermocouple Location 6.13.1 Air-to-Fuel Ratio Determination 6.14  Injector Flow Testing 6.14.1 Exhaust and Exhaust Back Pressure Systems 6.15 Blowby Flow Rate Measurement 6.16 Pressure Measurement and Pressure Sensor Location 6.17Reagents and Materials 7 Test Fuel 7.1 Engine and Condenser Coolant 7.2 Coolant Additive 7.3 Coolant Preparation 7.4 Pre-Test Cleaning Materials 7.5 Sealing and Anti-seize Compounds 7.6Test Oil Sample Requirements 8Preparation of Apparatus 9 Condenser Cleaning 9.1 Intake Manifold Cleaning 9.3 Cleaning of Engine Parts (other than the block and heads) 9.4 Engine Block Cleaning 9.5 Cylinder Head Cleaning 9.6 Engine Build-up Procedure 9.7  General Information 9.7.1  Special Parts 9.7.2  Hardware Information 9.7.3  Fastener Torque Specifications and Torquing Procedures 9.7.4 Parts Replacement 9.8 Engine Block Preparation 9.9 Piston Fitting and Numbering 9.10  Piston Ring Fitting 9.10.1 Pre-Test Camshaft and Lifter Measurements 9.11 Camshaft Bearing Installation 9.12 Camshaft Installation 9.13 Main Bearings 9.14  Crankshaft Installation 9.14.1  Main Bearing Cap Installation 9.14.2 Crankshaft Sprocket 9.15 Camshaft Sprocket and Timing Chain 9.16 Crankshaft End Play 9.17 Piston Pin Installation 9.18  Piston Installation 9.18.1 Harmonic Balancer 9.19 Connecting Rod Bearings 9.20 Engine Front Cover 9.21 Coolant Inlet Adapter 9.22 Oil Dipstick Hole 9.23 Oil Pan 9.24 Cylinder Head Assembly 9.25 Adjustment of Valve Spring Forces 9.26 Cylinder Head Installation 9.27 Hydraulic Valve Lifters 9.28 Pushrods 9.29 Valve Train Loading 9.30 Intake Manifold 9.31 Rocker Covers 9.32 Water Inlet Adapter 9.33 Condenser 9.34 Coolant Outlet Adapter 9.35 External Oil Cooling System 9.36 Oil Sample Valve 9.37 Ignition System 9.38 Throttle Body 9.39 Accessory Drive Units 9.40 Exhaust Manifolds, Water-Cooled 9.41 Engine Flywheel 9.42 Pressure Checking of Engine Coolant System 9.43 Lifting of Assembled Engines 9.44 Mounting the Engine on the Test Stand 9.45 External Cooling System Cleaning 9.46 Engine Coolant Jacket Cleaning (Flushing) 9.47 Coolant Charging 9.48 Test Oil Charging 9.49 Engine Oil Pump Priming 9.50Calibration 10 Laboratory and Engine Test Stand Calibration 10.1 Testing of Reference Oils 10.2 Reference Oil Test Frequency 10.3 Evaluation of Reference Oil Test Results 10.4 Status of Non-Reference Oil Tests Relative to Reference  Oil Test 10.5 Status of Test Stands Used for Non-Standard Tests 10.6 Data Acquisition and Control 10.7  Sample Rate 10.7.1  Measurement Accuracy 10.7.2  Temperature 10.7.3  Pressure 10.7.4  Flow 10.7.5  Speed 10.7.6  Mass 10.7.7  Measurement Resolution 10.7.8  System Time Response 10.7.9  Quality Index 10.7.10Engine Operating Procedure 11 Dipstick and Hole Plug 11.1 Dipstick Hole O-ring 11.2 Engine Start-up and Shutdown Procedures 11.3 Start-up 11.4 Scheduled Shutdown 11.5 Non-Scheduled Shutdowns 11.6 Oil Sampling 11.7 Oil Leveling 11.8 Air-to-Fuel-Ratio Measurement and Control 11.9 Air-to-Fuel Ratio Verification 11.10 Blowby Flow Rate Measurement 11.11 NOx Determinations 11.12 Data Recording 11.13 Initial Run (10 min) 11.14 Engine Oil Quality Testing (80 h) 11.15 Test Termination 11.16Determination of Test Results 12 Engine Disassembly 12.2 Preparation of Parts for Rating of Sticking, Deposits,  and Plugging 12.3 Piston Deposit Ratings 12.4 Post-Test Camshaft and Lifter Wear Measurements 12.5 End-of Test Used Oil Sample Testing 12.6 Viscosity Test 12.7 Testing Oil Samples for Wear Metals 12.8 Blowby Flow Rate Measurements 12.9 Oil Consumption Computation 12.10 Photographs of Test Parts 12.11 Retention of Representative Test Parts 12.12 Severity Adjustments 12.13 Determination of Operational Validity 12.14Report 13 Report Forms 13.1 Precision of Reported Units 13.4 Deviations from Test Operational Limits 13.3Precision and Bias 14Keywords 15Annexes  ASTM Test Monitoring Center – Organization Annex A1ASTM Test Monitoring Center – Calibration Procedures Annex A2ASTM Test Monitoring Center – Maintenance Activities Annex A3ASTM Test Monitoring Center – Related Information Annex A4Sequence IIIF Test Parts Replacement Guidelines Annex A5Sequence IIIF Determination Volume of Engine Oil in Pan Annex A6Sequence IIIF Test Fuel Analysis Annex A7Sequence IIIF Test Report Forms and Data Dictionary Annex A8Sequence IIIF Test Air-to-Fuel Ratio Control Flow Chart Annex A9Sequence IIIF Test Set Points and Control States Annex A10Sequence IIIF Quality Index Upper and Lower Values Annex A11Sequence IIIF Engine Oil Level Worksheet Annex A12Engine Build Worksheets Annex A13Blowby Flow Rate Determination Annex A14Safety Precautions Annex A15Sequence IIIF Blueprint Listing Annex A16Fluid Conditioning Module Components Annex A17Engine Oil Cooling System Configuration Annex A18Guidelines For Hardware Subject To First-In/First-Out Criteria Annex A19Appendixes  Sequence IIIFHD Test Procedure Appendix X1Sequence IIIFVIS Test Procedure Appendix X21.4 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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5.1 Investments in long-lived projects such as buildings are characterized by uncertainties regarding project life, operation and maintenance costs, revenues, and other factors that affect project economics. Since future values of these variable factors are generally not known, it is difficult to make reliable economic evaluations.5.2 The traditional approach to project investment analysis has been to apply economic methods of project evaluation to best-guess estimates of project input variables as if they were certain estimates and then to present results in single-value, deterministic terms. When projects are evaluated without regard to uncertainty of inputs to the analysis, decision-makers may have insufficient information to measure and evaluate the risk of investing in a project having a different outcome from what is expected.5.3 Risk analysis is the body of theory and practice that has evolved to help decision-makers assess their risk exposures and risk attitudes so that the investment that is the best bet for them can be selected.NOTE 1: The decision-maker is the individual or group of individuals responsible for the investment decision. For example, the decision-maker may be the chief executive officer or the board of directors.5.4 Uncertainty and risk are defined as follows. Uncertainty (or certainty) refers to a state of knowledge about the variable inputs to an economic analysis. If the decision-maker is unsure of input values, there is uncertainty. If the decision-maker is sure, there is certainty. Risk refers either to risk exposure or risk attitude.5.4.1 Risk exposure is the probability of investing in a project that will have a less favorable economic outcome than what is desired (the target) or is expected.5.4.2 Risk attitude, also called risk preference, is the willingness of a decision-maker to take a chance or gamble on an investment of uncertain outcome. The implications of decision-makers having different risk attitudes is that a given investment of known risk exposure might be economically acceptable to an investor who is not particularly risk averse, but totally unacceptable to another investor who is very risk averse.NOTE 2: For completeness, this guide covers both risk averse and risk taking attitudes. Most investors, however, are likely to be risk averse. The principles described herein apply both to the typical case where investors have different degrees of risk aversion and to the atypical case where some investors are risk taking while others are risk averse.5.5 No single technique can be labeled the best technique in every situation for treating uncertainty, risk, or both. What is best depends on the following: availability of data, availability of resources (time, money, expertise), computational aids (for example, computer services), user understanding, ability to measure risk exposure and risk attitude, risk attitude of decision-makers, level of risk exposure of the project, and size of the investment relative to the institution’s portfolio.1.1 This guide covers techniques for treating uncertainty in input values to an economic analysis of a building investment project. It also recommends techniques for evaluating the risk that a project will have a less favorable economic outcome than what is desired or expected.21.2 The techniques include breakeven analysis, sensitivity analysis, risk-adjusted discounting, the mean-variance criterion and coefficient of variation, decision analysis, simulation, and stochastic dominance.1.3 The techniques can be used with economic methods that measure economic performance, such as life-cycle cost analysis, net benefits, the benefit-to-cost ratio, internal rate of return, and payback.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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