Environmental Statement volume 4 - Chiltern Evergreen3

D5.5 MEASUREMENT SURVEYSD5.5.1Noise MeasurementsFreight TrainsFreight trains may haul a variety of different wagons and containers. Noisesource levels for an ‘average’ freight vehicle have been based onmeasurements carried out at Oddington Crossing (shown as NML 8 inFigure 6.1K). Measurements were made of 11 freight trains between the 26 thand 28 th of August 2009. Measurements were made at a height of 1.5 m inFreefield conditions, level with the façade of the property (at a distance of5.3 m from the track), in accordance with the guidance given in BS 7445. Theresults of these measurements are presented in Table D5.5. These were thenused to calibrate the noise model so that a source correction for a freightvehicle provided by CRN was chosen which best represented measured noiselevels (whilst not being quieter). The chosen freight vehicle was a Disc BrakedFreight Vehicle (4 axles) with a CRN correction value of +7.5 dB. Using thisCRN vehicle for a freight train hauled by a Class 66 loco produces a predictednoise level (SEL) at Oddington Crossing of 93 dBA. The average measurednoise level (SEL) of a freight train at Oddington Crossing was 92 dBA.Table D5.5Noise Level Measurements of Freight Trains at Oddington CrossingDateTimeNoise Level (SELfreefield), dBAFreight Train Type26.08.09 05.05 90 4M60 waste12.05 94 4V60 waste12.20 94 6A49 MoD14.35 91 6A48 MoD27.08.09 12.32 83 6A49 MoD14.35 90 6A48 MoD20.35 95 6M49 waste28.08.09 05.20 93 4M60 waste12.07 92 4V60 waste12.43 90 6A49 MoD14.34 85 6A48 MoDAverage (logarithmic) 92D5.5.2Vibration MeasurementsCurrently, the maximum line speed between Bicester and Oxford is 64 kph.This will increase to 161 kph in places if the Scheme goes ahead (seeTable D5.4). As a result, vibration levels produced by individual trains mayincrease. Therefore, a section of railway along the fast London Marylebone –Birmingham line was chosen to carry out vibration measurements. The trackon this route is modern, similar to the track that will be used in the Scheme.ENVIRONMENTAL RESOURCES MANAGEMENTD-32CHILTERN RAILWAYS