Federal Aviation Administration (FAA) National Sleep Study

Inclusion Criteria: * Subjects must currently live in a residence exposed to relevant levels of nocturnal aircraft traffic and have received a recruitment survey in the mail. * Only one subject per household will be eligible, selected pseudo-randomly as the person in the household who most recently celebrated a birthday. * In order to be eligible to participate in the in-home study, participants must have completed and returned the recruitment postal survey that was sent to their residence. Exclusion Criteria: Survey respondents interested in participating in the in-home sleep study are ineligible to participate if they: * are less than 21 years of age; * have a Body Mass Index (BMI) greater than 35 kg/m2 or less than 17 kg/m2; * have been diagnosed with a sleep disorder, including obstructive or central sleep apnea, narcolepsy, restless legs syndrome, or periodic limb movement syndrome; * frequently (3 or more times per week) use prescription or over the counter medication to aid sleep; * have a hearing impairment; * have a cardiac arrhythmia; * work night shifts (defined as working for at least 4 hours between 00:00 to 06:00); * have dependents that frequently require care during the night; * are pregnant; * previously participated in one of the pilot studies performed at Philadelphia airport or Atlanta airport; or * habitually use earplugs or play back sounds in the bedroom that could mask aircraft noise.