Section 120.708 - Warning Devices(A) Each location designated as high radiation area, and each entrance to such location, shall be equipped with easily observable warning lights that operate when, and only when, radiation is being produced.(B) Except in facilities designed for human exposure, each high radiation area shall have an audible warning device which shall be activated for 15 seconds prior to the possible creation of prompt radiation. Such warning device shall be clearly discernible in all high radiation areas.(C) Barriers, temporary or otherwise, and pathways leading to high radiation areas shall be posted in accordance with 105 CMR 120.227 and 120.247.