Evaluation of impulse noise criteria using human volunteer data

Four impulse noise auditory injury criteria adopted by NATO countries, name ly, the MIL-STD-1474D (USA), Pfander (Germany), Smoorenburg (Netherlands), and L-Aeq8 (France), are evaluated against human volunteer data. Data from subjects wearing single-hearing protection exposed to increasing blast over pressure effects were obtained from tests sponsored by the US Army Medical Research and Material Command. Using logistic regression, the four criteria were each correlated with the test data. The analysis shows that all four criteria are overly conservative by 9.6-21.2 dB for the subjects as tested. The MIL-STD-1474D for single-hearing protection is 9.6 dB lower than the o bserved injury threshold for 95% protection with 95% confidence for this pa rticular group of subjects as tested. Similar conclusions can be drawn for the other three criteria. (C) 2001 Acoustical Society of America.