In a crowd-filled venue, the ability to clearly understand emergency announcements and instructions can literally be a matter of life or death. That's why the National Fire Protection Association included a voice intelligibility requirement in NFPA 72, the National Fire Alarm and Signaling Code. Widely adopted by jurisdictions across the country, the code mandates mass notification systems for "acoustically distinguishable spaces" and specifies intelligibility standards for those spaces. As Boston's Communications Design Associates, Inc. recently found when designing a sound upgrade for the city's John B. Hynes Veterans Memorial Convention Center, Electro-Voice is the only loudspeaker manufacturer that can deliver the required intelligibility in high-ceilinged spaces requiring long-throw horns.