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While psychoacoustical methods to evaluate the sound attenuation of heating protective devices have been standardized (CSA Z94.2-M1984; ASA STD 1-1975) and proved to be practical for continuous noise, no standard exists for impulse noise. Microphone-based techniques seem to provide the best avenue for the measurement of impulse noise attenuation at the present time. This paper presents our progress in the design of a new artificial head simulating the relevant mechanical and acoustical parameters of the human head influencing the protected and unprotected eardrum sound pressure. These parameters include: (1) the diffraction of sound by the human head, (2) the mechanical impedance of human tissues, (3) the circumaural contours, (4) the external ear features such as pinna, ear canal, and eardrum impedance, and (5) the vibration of the head in the sound field. [Work supported by the Defence and Civil Institute of Environmental Medecine, Canada.] [ABSTRACT FROM AUTHOR]