Post on 31-Mar-2015
Federal AviationAdministrationEnvironmental
Prescreening TrainingModule 3
Noise Review
2Federal AviationAdministration
Noise Review June 25, 2013
Training Modules1. NEPA and CEQ
2. FAA Order 1050
3. Air Traffic Environmental – Noise Review
4. Environmental Screening Process Overview
3Federal AviationAdministration
Noise Review June 25, 2013
Module 3
Air Traffic Environmental – Noise Review
4Federal AviationAdministration
Noise Review June 25, 2013
Guidance “Significant” Impacts - Noise• Quantification of noise impacts
DNL Noise Exposure with
Proposed Action
Minimum Increase in DNL with Proposed
ActionChange in Noise Exposure Level Reference
FAA Order 1050.1E, Apdx. A, §14.314 CFR Part 150.21(2)(d)FICON 1992
FAA Order 1050.1E, Apdx A, §14.4c FICON 1992
FAA Order 1050.1E, Apdx A, §14.5e FAA Notice 7210.36045 to 60 dB 5.0 dB
Information Disclosed When Evaluating Air
Traffic Actions
65 dB 1.5 dBExceeds Threshold of
Significance
60 to 65 dB 3.0 dB
Considered When Evaluating Air Traffic
Actions
5Federal AviationAdministration
Noise Review June 25, 2013
Introduction
• Noise– What is noise?– Metrics used
• Impact Categories– What categories are examined for potential
significant impacts?• Noise sensitive Areas
– What are these areas?– Why are they important?
6Federal AviationAdministration
Noise Review June 25, 2013
Noise 101• One of the primary drivers for FAA air traffic
environmental studies is the potential impact of noise.– Noise is defined as the presence of unwanted
sounds– The basic unit is decibel (dB)– Noise measurements are logarithmic in nature– Most day-to-day sounds are between 30 and 100
dB.• Normal conversation at 3 feet is about 65 dB• An increase from 6dB to 10dB can be perceived as
doubling loudness
7Federal AviationAdministration
Noise Review June 25, 2013
Noise 101 (Cont.)
Typical Range of Outdoor Community Day-Night Average Sound Levels
8Federal AviationAdministration
Noise Review June 25, 2013
Noise 101 (Cont.)
• Several metrics are used to measure and express noise levels.– DNL: which is Day-Night Average Sound Level and
is the most commonly used metrics. – Lmax: which is the Maximum A-Weighted Sound
level– SEL: which is Sound Exposure Level or Single
Event Noise Exposure Level.– Leq: which is Equivalent Sound Level– CNEL: Community Noise Equivalent Level. Only
used in the state of California.
9Federal AviationAdministration
Noise Review June 25, 2013
Noise 101 (Cont.)
Comparison of Different Sounds
10Federal AviationAdministration
Noise Review June 25, 2013
Noise 101 (Cont.)
Relationship among Noise Metrics
11Federal AviationAdministration
Noise Review June 25, 2013
Noise 101 (Cont.)
12Federal AviationAdministration
Noise Review June 25, 2013
Noise 101 (Cont.)
Levels for which speech intelligibility is impacted
13Federal AviationAdministration
Noise Review June 25, 2013
Noise 101 (Cont.)
Addition of Two Decibel Levels
14Federal AviationAdministration
Noise Review June 25, 2013
Noise 101 (Cont.)
Examples of Sound Level Averaging
15Federal AviationAdministration
Noise Review June 25, 2013
Noise 101 (Cont.)
Percentage of Population Highly Annoyed by General Transportation Noise
16Federal AviationAdministration
Noise Review June 25, 2013
Noise Sensitive Areas and Significance
• An area where noise interferes with normal activities associated with its use.
• E.g.:• Residential• Specified areas within national parks• National wildlife refuges• Schools• Places of worship• Cultural and Historical sites
17Federal AviationAdministration
Noise Review June 25, 2013
Noise Sensitive Areas and Significance (Cont.)
• Noise from airplanes and helicopters, noise sensitive areas include such areas within the Day Night Level (DNL) 65 noise contour.
• An impact on noise levels of noise-sensitive areas is considered an extraordinary circumstance and requires additional environmental analysis.
18Federal AviationAdministration
Noise Review June 25, 2013
How Can We Identify Noise Sensitive Areas?• Check various sources: (e.g., airnav.com)• Check with local Airports District Office (ADO)
19Federal AviationAdministration
Noise Review June 25, 2013
How Can We Identify Noise Sensitive Areas? (Cont.)
20Federal AviationAdministration
Noise Review June 25, 2013
Impact Categories (Cont.)
Take a few minutes to refresh on Noise section in 1050.1E
21Federal AviationAdministration
Noise Review June 25, 2013
Impact Categories (Cont.)
Noise• For aviation noise analysis, the FAA has determined
that cumulative noise exposure to individuals resulting from aviation activities must be expressed in terms of annual day/night average sound level (DNL)
• If significant noise impacts are expected, then detailed noise analyses must be performed.
22Federal AviationAdministration
Noise Review June 25, 2013
Impact Categories (Cont.)
Noise• A significant noise impact would occur if analysis shows
that the proposed action will cause noise sensitive areas to experience an increase in noise of DNL 1.5 dB or more at or above DNL 65 dB noise exposure when compared to the no action alternative for the same timeframe.
23Federal AviationAdministration
Noise Review June 25, 2013
• Quantification of noise impacts
Guidance “Significant” Impacts - Noise
DNL Noise Exposure with
Proposed Action
Minimum Increase in DNL with Proposed
ActionChange in Noise Exposure Level Reference
FAA Order 1050.1E, Apdx. A, §14.314 CFR Part 150.21(2)(d)FICON 1992
FAA Order 1050.1E, Apdx A, §14.4c FICON 1992
FAA Order 1050.1E, Apdx A, §14.5e FAA Notice 7210.36045 to 60 dB 5.0 dB
Information Disclosed When Evaluating Air
Traffic Actions
65 dB 1.5 dBExceeds Threshold of
Significance
60 to 65 dB 3.0 dB
Considered When Evaluating Air Traffic
Actions
24Federal AviationAdministration
Noise Review June 25, 2013
Questions?