ASTM E1110 - 06(2019)

    Standard Classification for Determination of Articulation Class

    Active Standard ASTM E1110 | Developed by Subcommittee: E33.02

    Book of Standards Volume: 04.06


      Format Pages Price  
    PDF 2 $44.00   ADD TO CART
    Hardcopy (shipping and handling) 2 $44.00   ADD TO CART



    Significance and Use

    4.1 Each weighting factor given in Table 1 represents the fraction of overall speech intelligence contained within the associated one-third octave frequency band.

    4.2 The weighting factors in Table 1 are obtained by multiplying each individual one-third octave band weighting factor of ANSI S3.5-1969 by 300. Articulation class (AC) values are thus related to but distinctly different from articulation index (AI) values. In particular, the AC considers only the effect of signal attenuation; while the AI considers such additional factors as speech level and spectrum and background sound level and spectrum.

    Note 2: The AC is similar to the DAI rating proposed by Warnock6 and has been shown to correlate with AI values derived from ANSI S3.5, except where the AI approaches 1 or 0 (AI values range between 1 and 0 and approach 0 with increasing privacy and nonintelligibility). Articulation class values give the reverse. They usually exceed 100 and increase with increasing privacy and nonintelligibility. Extensive comparison between AC ratings and subjective judgments of open-plan speech privacy has not yet been accomplished.

    1. Scope

    1.1 This classification provides a single figure rating that can be used for comparing building systems and subsystems for speech privacy purposes. The rating is designed to correlate with transmitted speech intelligence between office spaces.

    1.2 Excluded from the scope of this classification are applications involving female speakers or children,2 languages other than English, and sound spectra other than speech. Thus excluded, for example, would be comparisons of building systems or subsystems for their effectiveness in reducing transmitted noise from machinery, industrial processes, bowling alleys, music rooms, places of entertainment, and the like.

    Note 1: Published work by Pearsons, et al, may eventually permit the restriction on female speakers to be relaxed.3

    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.


    2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.

    ASTM Standards

    E1111 Test Method for Measuring the Interzone Attenuation of Open Office Components


    ICS Code

    ICS Number Code 17.140.01 (Acoustic measurements and noise abatement in general)

    UNSPSC Code

    UNSPSC Code 30141601(Acoustical insulation)


    Referencing This Standard
    Link Here
    Link to Active (This link will always route to the current Active version of the standard.)

    DOI: 10.1520/E1110-06R19

    Citation Format

    ASTM E1110-06(2019), Standard Classification for Determination of Articulation Class, ASTM International, West Conshohocken, PA, 2019, www.astm.org

    Back to Top