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4.1 The purpose of the LIR rating is to describe the low-frequency impact noise, often referred to as “thudding,” primarily generated by footfall on lightweight structures. The rating increases as the impact sound attenuation of the floor-ceiling structure increases. This rating has been shown to correlate with subjective reaction3,4 and can be used to evaluate and compare the low-frequency impact noise performance of assemblies.4.2 The LIIC rating can be used for relative comparison and to rank-order the low-frequency performance of assemblies within a given test laboratory.5 The reproducibility of LIIC between laboratories has not been measured, and the relationship between laboratory and field ratings (LIIC and LIR) is not assumed or established.NOTE 1: The tendency for measurement uncertainty to increase at low frequencies should be considered when utilizing metrics of classification standard.NOTE 2: This classification does not replace Classification E989 (Impact Insulation Class) and is not interchangeable with it. For example, the LIIC rating of an assembly does not determine its IIC rating and cannot be used to show compliance with an IIC requirement. The expectation is that the low-frequency ratings would be reported alongside the existing ratings.4.3 This classification shall only be used with one-third-octave-band data.1.1 This classification provides methods for calculating single-number ratings of low-frequency impact noise transmission, based on one-third-octave-band impact noise levels as described in Test Methods E492 and E1007.1.2 This classification defines ratings that are not defined in other standards. Other standards may define additional ratings based on the methods of this classification.1.3 Units—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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定价： 590元 / 折扣价： 502 元 加购物车

定价： 1957元 / 折扣价： 1664 元

定价： 515元 / 折扣价： 438 元 加购物车

4.1 The rating increases as the impact sound attenuation of the floor ceiling structure increases. The rating can be used by architects, builders, and specification and code authorities for acoustical design purposes in building constructions.4.2 The rating strictly only applies to excitation by the standard tapping machine defined in Test Methods E492 and E1007. It does not deal with low frequency sounds below 100 Hz that are typically generated below lightweight joist floors when they are walked on. Nor does it deal with the squeaking, crunching or rattling sounds that can occur in joist construction when elements in the construction are loose and occupants walk on the floor.4.3 This classification shall only be used with one-third octave band data.1.1 This classification provides a method for determining a rating that can be used to compare the levels of impact noise generated by a standard tapping machine and transmitted through different floor-ceiling assemblies.1.2 The name given to the rating is assigned by the test method that invokes this classification.1.3 This classification is applicable only to one third octave band impact noise data obtained using the standard tapping machine described in Test Methods E492 and E1007.1.4 Test methods that invoke this classification include:1.4.1 Test Method E492 – the single-number rating is called impact insulation class (IIC).1.4.2 Test Method E1007 – the single-number ratings are called apparent impact insulation class (AIIC), impact sound rating (ISR), and normalized impact sound rating (NISR).1.4.3 Test Method E2179 – the single-number rating is called the change in impact insulation class (ΔIIC).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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定价： 156元 / 折扣价： 133 元 加购物车

4.1 Evaluation of Environmental Noise—Environmental noise is evaluated by comparing a measurement or prediction of the noise to one or more criteria. There are many different criteria and ways of measuring and specifying noise, depending on the purpose of the evaluation. Some evaluations are limited to determining compliance with existing regulations or ordinances. Others are done in the absence of such requirements or to supplement regulatory evaluations where the regulations do not address fully or at all the issues of concern.4.2 Selection of Criteria—This guide provides information useful in selecting the appropriate criteria and measurement method to evaluate noise. In making the selection, the user should consider the following: regulatory or legal requirements for the use of a specific criterion; purpose of the evaluation (regulatory compliance, compatibility, activity interference, aesthetics, comfort, annoyance, health effects, hearing damage, etc.); types of data that are available or could be available (A-weighted, octave band, average level, maximum level, day-night level, calibrated recordings including .wav files from which various measurements could be made, etc.); and available budget for instrumentation and manpower to obtain that data. After selecting a measurement method, the user should consult appropriate references for more detailed guidance (1).74.3 Objective versus Subjective Evaluations—This guide discusses objective sound criteria based on measurements and regulations based on such. Some local noise ordinances are based solely or partially on subjective judgements of noise. Enforcement of these can be easily challenged and, in some jurisdictions, they are not permitted. These are not further considered in this guide. One way to address such situations is to evaluate the sound based on reasonable objective criteria.4.4 Soundscape Methodology—The overall sound environment as perceived outdoors is often called a soundscape. Soundscapes have both objective (quantitative) and subjective (qualitative) attributes. A soundscape evaluation methodology is evolving which includes methods and criteria that rely extensively on qualitative factors, both acoustical and non-acoustical, while including requirements for quantitative sound measurement. Two basic tenets of quantitative soundscape measurements are that the ambient sound at a location is comprised of a combination of specific acoustic events that can be measured individually and in combinations; and that the sounds should be measured using methods that represent the ways in which they are perceived by people. Development of such measurement methods specifically for soundscape studies is a part of ongoing research and is not specifically discussed in this document.1.1 This guide covers many measurement methods and criteria for evaluating environmental noise, some of which are required to be used for specific purposes by governmental regulations. It is intended to provide users who may not be familiar with them with an overview of the wide variety of available methods and criteria. It includes the following:1.1.1 The use of weightings, penalties, and adjustment or normalization factors;1.1.2 Types of noise measurements and criteria, indicating their limitations and best uses;1.1.3 Sources of criteria;1.1.4 Recommended procedures for criteria selection;1.1.5 A catalog of sources of selected available criteria; and1.1.6 Suggested applications of sound level measurements and criteria.1.2 Criteria Selection—Thorough evaluation of noise issues requires consideration of many characteristics of both the sound and the environment into which it is introduced. This guide will assist users in selecting criteria for the following:1.2.1 Evaluating the effect of existing or potential outdoor sounds on a community considering the magnitude and other characteristics of the sound and environment;1.2.2 Establishing or revising local noise ordinances, codes, or bylaws, including performance standards in zoning regulations; and1.2.3 Identifying and evaluating compliance with regulatory requirements that do not specify an acoustical measurement method or criterion or which are unclear.1.3 Reasons for Criteria—This guide discusses the many reasons for noise criteria, ways sound can be measured and specified, and advantages and disadvantages of the most widely used types of criteria. The guide refers the user to appropriate documents for more detailed information and guidance. Users needing further general background on sound and sound measurement are directed to the books listed in the References section.1.4 Criteria in Regulations—Certain criteria are specified to be used by government regulation, law, or ordinance for specific purposes. Any investigation or evaluation of a community noise issue must start with identifying applicable regulations and evaluating compliance with them. This document discusses but is not limited to regulations and ordinances. Due to the wide variation in local regulations, those are discussed more generally, and specific criteria are provided only from national government regulations. Regulations typically specify measurement methods and criteria for purposes of the regulation. Local ordinances must be written for ease of enforcement and cannot address all situations satisfactorily without becoming too complex. Such ordinances are also often prepared without competent guidance and can be too restrictive in some cases and not restrictive enough in others. Other regulations that determine government spending for noise control must balance that cost to the general public against impacts on individuals.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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1. Scope This International Standard specifies a method for the measurement of the noise at the position of the operator(s) of a tractor or machine used in agriculture and forestry. The measured noise relates only to the basic machine and applies to se

定价： 546元 / 折扣价： 465 元

3.1 Resistance or voltage values alone do not provide sufficient detail for an engineering evaluation of contact noise. This practice lists the test conditions that should be reported with noise measurements and indicates some conditions (open circuit voltages, currents, etc.) that have been used for quality control and research studies. The use of these practices should provide sufficient detail for an engineering interpretation of the noise data and allow the tests to be repeated by another laboratory.1.1 This practice describes the practices and factors considered to be most important in the measurement of electrical contact noise of sliding contacts.1.2 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 become familiar with all hazards including those identified in the appropriate Safety Data Sheet (SDS) for this product/material as provided by the manufacturer, to establish appropriate safety, health, and environmental practices, and determine the applicability of regulatory limitations prior to use.1.3 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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定价： 515元 / 折扣价： 438 元 加购物车

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Update #1 was published as notification that this is now a National Standard of Canada This PDF includes Update #1 1. Scope 1.1 This Standard is intended for manufacturers and purchasers of machinery sold in, or exported from, Canada. It is also

定价： 546元 / 折扣价： 465 元