point cover jan 13 - Boston Redevelopment Authority

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Expanded_PNF\04_Environmental_FINAL.do
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Vanasse Hangen Brustlin, Inc.
The Point, Boston
allowable sound levels based upon the land use affected by the proposed development. Table 4-9 summarizes
the noise standard for the various land uses. These maximum allowable sound levels should not be exceeded.
Table 4-9
City of Boston Zoning District Noise Standards, dB(A)
Daytime
All Other Times
Land Use Zone District
(7:00 AM – 6:00 PM)
(6:00 PM – 7:00 AM)
Residential 60 50
Residential/Industrial 65 55
Business 65 65
Industrial 70 70
Source: Regulations for the Control of Noise in the City of Boston, Air Pollution Control Commission.
For a residential zoning district, the maximum noise level affecting residential uses shall not exceed the
Residential Noise Standard. The residential land use noise standard is 60 dB(A) for daytime periods (7:00 AM
to 6:00 PM) and 50 dB(A) for nighttime conditions (6:00 PM to 7:00 AM).
The City of Boston’s regulations on construction sound levels state that operation of any construction devices,
excluding impact devices, may not exceed a L10 sound level of 75 dB(A) or Lmax sound level of 86 dB(A) at a
residential land use during any time period.
Noise Analysis Methodology
The noise analysis evaluated the potential sound level impacts associated with the Project’s operations, such
as rooftop mechanical equipments and loading activities. The noise analysis included measurements of
existing ambient background sound levels and an evaluation of potential project generated sound levels. The
study area was evaluated and sensitive receptor locations were identified. The noise analysis determined the
sound level at sensitive receptor locations.
A noise monitoring program was developed to measure existing sound level in the vicinity of the Project site.
The noise analysis evaluated sound levels associated with potential rooftop mechanical equipments, such as
HVAC units, cooling towers, and emergency generators. The noise analysis determined the maximum sound
levels from the rooftop mechanical equipments that will result in sensitive receptor locations meeting City of
Boston’s noise standards. Since the Project is in the early stages of the design process, specific technical
specifications of the rooftop mechanical equipments were not available at this time. The maximum sound
levels are based on preliminary assumptions on the size and number of units of the potential rooftop
mechanical equipments.
The City of Boston’s noise criteria were used as the basis for determining the maximum sound levels allowed
from each set of equipment on the building rooftop. Applying the properties of sound propagation over hard
ground, the noise analysis projected sound levels to sensitive receptor locations from the Project to determine
the overall maximum sound level that would be allowed from the combined group of rooftop mechanical
equipment. The noise analysis assumed sound level reductions due to distance and building blockages. The
sensitive receptor locations included ground level apartments at nearby residential buildings along Boylston
4-31 Environmental Protection