2019 California Standards for Accessible Design Guide (effective January 1, 2020 with July 1, 2021 amendments)
11B-706.1 General.
Assistive listening systems required in assembly areas, conference and meeting rooms shall comply with Section 11B-706.
[2010 ADA Standards] 706.1 General. Assistive listening systems required in assembly areas shall comply with 706.
The technical standards for assistive listening systems describe minimum performance levels for volume, interference, and distortion. Sound pressure levels (SPL), expressed in decibels, measure output sound volume. Signal-to-noise ratio (SNR or S/N), also expressed in decibels, represents the relationship between the loudness of a desired sound (the signal) and the background noise in a space or piece of equipment. The higher the SNR, the more intelligible the signal. The peak clipping level limits the distortion in signal output produced when high-volume sound waves are manipulated to serve assistive listening devices.
Selecting or specifying an effective assistive listening system for a large or complex venue requires assistance from a professional sound engineer. The federal Access Board has published technical assistance on assistive listening devices and systems. ◼
User Comments/Questions
Add Comment/Question