This project will develop and qualify a new assistive technology to aid persons who are blind. The Emergency Egress Locator (EEL) will provide guidance to exits under emergency conditions. The illumination from ordinary exit signs will be modulated to carry the guidance information while still being totally visible and functional as an exit sign. Persons who are blind will carry or wear a receiver based on a cellphone as a computing platform which processes the optical signal from the exit sign and provides audio guidance to the person who is blind. If some exits are blocked by emergency, the networked EEL exit signs will reconfigure themselves to lead users to a safe area. EEL will be inexpensive and easy to implement because it will use existing exit signs. EEL will be demonstrated in a commercial facility and evaluated with blind travelers. Its assistive capability and comparison with other assistive technologies will be quantitatively measured. This project will develop a system to help persons who are blind find their way to exits safely and quickly in case of emergency. Ordinary exit signs will be modified to provide location and guidance to persons who are blind and cellphone based locators will provide wayfinding audio guidance. Persons who are blind will be able to travel more safely and independently. ? ? ? ?