The standard defines several single-number quantities to evaluate acoustic performance: Spatial Decay Rate of Speech ( D2,Scap D sub 2 comma cap S end-sub
): A newer metric that has largely replaced "privacy distance" in recent revisions, indicating the distance at which speech becomes comfortable for others. Distraction Distance ( rDr sub cap D DIN EN ISO 3382 3 E 2021 02 pdf
): The A-weighted sound pressure level of speech at a 4-meter distance, indicating how much nearby surfaces reflect sound. Comfort Distance ( rCr sub cap C Unlike Part 2, which focuses on temporal decay
(often cited as the 2022 international version) is the primary standard for measuring room acoustic parameters in unoccupied open-plan offices . Unlike Part 2, which focuses on temporal decay (reverberation), Part 3 focuses on spatial decay , or how sound levels drop as you move away from a speaker. Key Acoustic Parameters Unlike Part 2