Study objectives: To quantify the snoring sound intensity levels generated by individuals during polysomnographic testing and to examine the relationships between acoustic, polysomnographic, and clinical variables. Design: The prospective acquisition of acoustic and polysomnographic data with a retrospective medical chart review. Setting: A sleep laboratory at a primary care hospital. Participants: All 1,139 of the patients referred to the sleep laboratory for polysomnographic testing from 1980 to 1994. Interventions: The acoustic measurement of snoring sound intensity during sleep concurrent with polysomnographic testing. Measurements and results: Four decibel levels were derived from snoring sound intensity recordings. L-1, L-5, and L-10 are measures of the sound pressure measurement in decibels employing the A-weighting network that yields the response of the human ear exceeded, respectively, for 1, 5, and 10% of the test period. The Leg is a measure of the A-weighted average intensity of a fluctuating; acoustic signal over the total test period. L-10 levels above 55 dBA were exceeded by 12.3% of the patients. The average levels of snoring sound intensity were significantly higher for men than for women. The levels of snoring sound intensity were associated significantly with the following: polysomnographic testing results, including the respiratory disturbance index (RDI), sleep latency, and the percentage of slow-wave sleep; demographic factors, including gender and body mass; and clinical factors, including snoring history, hypersomnolence, and breathing stoppage, Men with a body mass index of > 30 and an average snoring sound intensity of > 38 dBA were 4.1 times more likely to have an RDI of > 10. Conclusions: Snoring sound intensity levels are related to a number of demographic, clinical, and polysomnographic test results, Snoring sound intensity is closely related to apnea/hypopnea during sleep. The noise generated by snoring can disturb or disrupt a snorer's sleep, as wed as the sleep of a bed partner.