Glossary of Terms


Acoustical Test Plan: The document that describes the types of homes located in the project area and the process to conduct the acoustical test that will be used to document the interior noise level.

Acoustical: Conditions or products related to hearing, noise, or sound.

Bid Package: A group of houses assembled together into one construction contract.

Condensation: The result of high humidity (moisture in the air) that produces a “fog” when it hits a colder surface such as a glass window.

Day-Night Level (DNL): Average annual sound levels that represent the sound levels over a 24-hour period, while considering quiet periods as well as aircraft over-flights. For flights that occur after 10:00 p.m. and before 7:00 a.m., these events receive a 10 dB penalty. The DNL noise exposure contours in the affected residential neighborhoods are 75 DNL to 65 DNL.

Decibel (dB): A unit of measure for the vibration (low rumble or high whistle) and strength (soft or loud) of sound waves. The higher the decibel level (vibration and strength), the louder the sound. Most sounds we experience in our day-to-day lives vary between 30 dB (a typical bedroom at night) and 100 dB (inside a nightclub).

Eligibility: Qualified to participate in the Logan RSIP by having a home or property located in the project area. Homeowner Participation Agreement: An agreement between a homeowner and the Massport that authorizes the installation of specific sound insulation treatments at a given residential property.

Federal Aviation Administration (FAA): The branch of the federal government that provides funding and oversight of the Logan RSIP.

Logan: Boston Logan International Airport.

Massport: Massachusetts Port Authority, sponsor of the Logan RSIP.

Project Team: All personnel, including program managers, architects, and engineers representing the Logan RSIP who will go to each home to gather information and make treatment recommendations.

Noise Level Reduction (NLR): Noise level reduction is measured in decibels and is defined as a constant numerical value between the interior noise level and the exterior noise level. This measurement is taken before and after acoustical treatments to determine the overall improvement in noise level reduction. This value will be used to compare the post construction interior noise levels in the home to the FAA goal of below 45 DNL (Day-Night Level).

Noise Paths: The areas where environmental noise can travel from the outside through the home’s construction, with the greatest flow through doors, windows, vents, and/ or lightly constructed wall and ceiling assemblies.

Punch List: A “to do” list made near the completion of construction work indicating the items that remain unfinished, or that do not meet the quality requirements specified in the scope of work. The Punch List must be satisfied prior to 100% completion.

RSIP: Residential Sound Insulation Program.

Sound Insulation: The application of residential sound insulation can include some or all of the following: replacing or supplementing windows and doors; installing attic insulation; caulking; and sealing. FAA residential sound insulation projects, including the Logan RSIP, are voluntary projects. Project participation is not a requirement.

Sound Level Meter: The instrument used by the acoustical consultant to measure the sound or “noise” that is occurring inside and outside the home.