As of 2006, standards for loop system performance were heavily revised by the International Electrotechnical Commission (IEC). The more complex requirements of IEC60118-4 increased performance standards for audio induction loop systems in any assistive listening application. Adopted around the world as the reference for performance, the new code impacted the specification, design, installation and maintenance of the systems to a point that any seat in a looped space will deliver the same quality of audio signal.
Unfortunately, prior to 2006, some of the hearing loop systems installed in the US delivered less-than-satisfactory performance. Currently, the best practice for designers and installers is to guarantee to commission a loop project to meet IEC60118-4 standards.
In 2010, the ADA rules for effective communications in public spaces were also upgraded. Since then, you will find that small meeting spaces, as well as extremely large theaters, have been looped properly and that the audio quality is beautiful — with no “dead spots” at any seats. Looping for smaller spaces (with privacy) is also more popular now as evidenced by the 1:1 conversational loops that have been installed in many places.
Note: “The ADA requires that title II entities (State and local governments) and title III entities (businesses and nonprofit organizations that serve the public) communicate effectively with people who have communication disabilities. The goal is to ensure that communication with people with these disabilities is equally effective as communication with people without disabilities.”