Acoustics and ADA

The Americans with Disabilities Act (ADA) has stirred up much controversy over the past year. This article will provide some practical guidelines for the public accommodations portion of these requirements. The new ADA hearing assistance requirements are not really new for Californians since the 1988 UBC, with the California Title 24 Amendment, has required hearing assistance systems.

The following summaries should help unravel the confusion surrounding these requirements.

Title 24 Section 611 (f) requires:

* Assembly areas with permanently installed public address systems provide assistive listening systems for people with hearing impairments.
* Exceptions: 1.This does not apply to systems used exclusively for paging, or background music, or a combination of these two uses. 2. Public and private schools are exempt from the requirements of this section.

The number of personal receivers required is based upon the capacity of the assembly area as follows:

Capacity # Receivers
1 to 99 0
100 to 200 8
201 to 300 12
301 to 400 16
401 to 500 20
over 500 20 + 1 for each additional 100 seats

ADA Section III-7.5180 Assembly Areas requires:

  • Fixed seating assembly areas that accommodate 50 or more people OR have audio-amplification systems must have a permanently installed assistive learning system.
  • Other assembly areas (not covered in above) must have a permanent system OR an adequate number of electrical outlets or other wiring to support a portable system.
  • A special sign indicating the availability of the system is required.
  • The minimum number of receivers must be equal to 4% of the total number of seats, but never less than two.

Because facilities will always be required to implement the “strictest” of the two codes we recommend the following as a guideline when designing audio-amplification requirements:

Capacity # Receivers
1 to 49 2
50 to 74 3
75 to 99 4
100 to 200 8
201 to 300 12
301 to 400 16
401 to 500 20
over 500 20 + 1 for each additional 100 seats

The bottom line, as put by the America Speech-Language-Hearings Association’s response to the ADA was:

“Ask people about their needs, show respect and sensitivity, use what works (not necessarily what is most expensive), and use your resources creatively and effectively.”

From a design perspective, any time an audio system that is used for speech reinforcement or audio playback is part of your contract documents, an assistive listening system should be part of the design.

(c) Thorburn Associates 1992