Rationale

The current E2638 standard measurement methodology is orientated towards the assessment of speech security, yet the calculation method is frequently used to evaluate non-secure speech privacy. No changes are proposed to the measurement or calculation methodology for secure speech assessment. However, this work item proposes to: (a) introduce text to separate speech security from other non-secure speech privacy categories; (b) introduce text to separate intentional listening (deliberate eavesdropping) from unintentional listening (for example, a worker perceiving speech not intended for them while at their normal workstation); (c) create a separate test methodology for non-secure speech and unintentional listening (i.e. not requiring measurement at the separating partition); (d) update the interpretative table in Annex X2.1 to include percentages of time audibility and intelligibility thresholds may be exceeded based on statistical likelihood of occurrence; and (e) Add new interpretative table for non-secure speech based on recent ASHRAE subjective response study.