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long,
If the construction site is linear in shape (that is, thin and substantially uniform in width, but not necessarily straight) with a length to width ratio exceeding 5:1, only the dominant portion of the site shall be considered for the purpose of determining the notional
source position. The dominant portion is defined as the portion of the linear site closest to the NSR and having a length to width ratio of 5:1.
If part of the construction site is linear in shape then such part shall
be subject to a separate assessment for a separate CNP, at the discretion
of the Authority.
If the construction site is large such that the notional source position would be greater than 50 m from the point on the site boundary
nearest to the NSR the position shall be taken to be a point 50 m from
that point on the site boundary measured along the line between the
approximate geographical centre of the site and the point on the site
boundary nearest to the NSR.
If in the opinion of the Authority the site is of such shape or dimensions that the procedure outlined above cannot readily be applied or
if such application would lead to an inappropriate notional source
position the Authority may select such a notional source position as it
considers appropriate in the circumstances.
If the Authority is satisfied that any itm of PME is to remain
in substantially the same position, and the particular item and its
position has been specified by the applicant, the actual position may be
used in conjuction with the notional source position for all other items
of PME in the calculation of distance attenuation in Step 9.
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2.8 Step 8
Sound Power Levels for Items of Powered Mechanical
Equipment (PME)
The sound power levels in dB(A) of each of the items of PME
intended for use on the construction site shall be obtained from Table 3.
If any item of PME intended for use on the construction site does not
appear in Table 3 the Authority may make use of such sound power level as it considers appropriate.
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