CROWN COPYRIGHT / HEALTH & SAFETY LABORATORY / SCIENCE PHOTO LIBRARY CROWN COPYRIGHT / HEALTH & SAFETY LABORATORY / SCIENCE PHOTO LIBRARY
Echo-free room. Dummy wearing ear defenders stands in an echo-free (anechoic) chamber. A loud speaker is at the far end of the room, whilst a microphone stands at left. The walls of the chamber are made of glass-fibre wedges which are designed to absorb noise so that sounds are not reflected. The chamber may be used to test the effectiveness of the ear defenders by comparing the sound levels in the room with those in the dummy's ears. CROWN COPYRIGHT UNDER LICENCE FROM THE HEALTH & SAFETY LABORATORY & CONTROLLER OF HER MAJESTY'S STATIONERY OFFICE.
Model release not available. Property release not required.