15 Noise and Vibration

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2 15 Noise and Vibration Chapter Summary Key features Ambient noise levels measured at the nearest residential receptors are typically in the range of L Aeq,T, which is relatively high, a consequence of the city centre location. Potential Impact Mitigation There are unlikely to be any significant impacts for the nearest residential receptors due to construction noise and vibration from the site or construction traffic; There is unlikely to be any significant impact from operational noise provided appropriate mitigation is included in the detailed design; Ventilation and fixed plant are to be designed to ensure compliance with noise limits specified for the nearest residential receptors. Residual Impacts No significant residual effects are anticipated. Introduction 15.1 This chapter provides an assessment of the potential noise and vibration impacts of the proposed development on the following sensitive receptors: Residential flats at Cambridge, Crescent, Galton and Norton Tower; Residential properties at Vincent House and 29 Acorn Grove (haul road noise only); Commercial premises at Baskerville House, the International Conference Centre (ICC), the former municipal Bank and Central House; The REP building (vibration only); The Hall of Memory (vibration only); and Underground rail tunnel (vibration only) The assessment identified four different noise and vibration impacts that could occur from the proposed development. These are: Construction noise, including plant, machinery and haul road noise; Construction vibration from piling or drilling bore holes; 15-1

3 Operational noise associated with the new Studio Theatre and the increase in the number of people visiting the site; and Operational noise due to fixed plant A baseline noise survey has been carried out to assess the existing noise climate at the nearest receptors An introduction to the noise and vibration terminology used in this report is provided in Appendix Methodology Baseline Noise Survey 15.5 A combination of manned and unmanned baseline noise measurements were taken at various locations around the application site, as shown in Figure 15.1, between the 1 st and 12 th May This included long-term noise measurements at Baskerville house, which was considered to be the most appropriate secure location that was suitably representative of the nearest noise sensitive receptors Weather conditions during monitoring remained within the limits of BS , i.e. low winds and occasional light precipitation. Table 15.1 provides a summary of the noise monitoring locations. Table 15.1 Summary of Noise Monitoring Locations Noise Monitoring Location Short or Long Term Manned or unmanned Representative Noise Sensitive Receptor ST1 Short-term Manned 2 nd Floor Cambridge/Crescent Tower* ST2 Short-term Manned Base Cambridge/Crescent Tower ST3 Short-term Manned Top of Cambridge/Crescent Tower LT1 Long-term Unmanned Baskerville House + * measurement taken in City Centre Gardens north of Cambridge Road at the approximate height of the 2 nd floor. + also considered representative of International Conference Centre, the Bank and Central House 15.7 Details of the equipment used to carry out the assessment are provided in Appendix Construction Noise 15.8 Permissable noise levels generated by construction activities are regulated in accordance with numerous European directives and on site construction noise is subject to Local Authority control, although no UK national noise limits exist. Guidance on acceptable noise levels is provided in British Standard BS 5228: Noise and vibration control on construction and open sites The plant to be used and their estimated on-times (the percentage of time that an item of plant is operational per hour) are given in Appendix Sound power levels for each 15-2

4 piece of equipment have been sourced from BS All noise predictions assume a worst case scenario with all plant at the closest appropriate location to the relevant receptor. However, predictions take into account that plant and machinery could move during the day over a range of 100 m which is the approximate width of the site. The topography is assumed to be flat between the construction activities and the receptors, with line-of-sight between the two Construction noise levels have been calculated according to the procedures given in BS For daytime and night time construction works the significance of the impact can be assessed against the ambient noise levels. The method for this type of assessment is given in Table E.1 of BS This provides a methodology for calculating whether a significant impact is likely, based on assessment with prescribed threshold values The noise levels generated by construction activities and experienced by nearby sensitive receptors, such as residential properties, depends upon a number of variables, the most significant of which are: The noise generated by plant or equipment used on site, generally expressed as sound power levels (L w ); The periods of operation of the plant on the site, known as its on-time ; The distance between the noise source and the receptor; and The attenuation provided by ground absorption and any intervening barriers. Construction Noise Haul Road Separate noise level predictions have been undertaken for construction traffic on the site access road using the Haul Road methodology in BS The predictions are based on an hourly rate of five HGVs using Cambridge Street, King Edwards Road and Summer Hill Street. This is based on information provided by Carillion (the construction contractor for the proposed development) 3 which identifies a maximum of 52 deliveries to the site per day. No screening corrections have been applied and a vehicle speed of 40 km/hr has been assumed. Construction Vibration Surface plant such as cranes, compressors and generators are not recognised as sources of high levels of environmental vibration and reference to Figure 1 of Control of Vibration and Noise during Piling 4 confirms that even at 10 m, peak particle velocities (ppv) significantly less than 5 mms -1 are generated by such plant. For example, the indication is that a bulldozer would generate a ppv of approximately 0.6 mms -1 and a heavy lorry on a poor road surface would generate a ppv of less than 0.1 mms -1 at 10 m. These values are significantly below the 5mms -1 limit at which even cosmetic building damage becomes likely. Therefore vibration from mobile construction plant has been excluded from the scope of this assessment. 15-3

5 15.15 BS 5228 provides methods for estimating vibration from driven and vibratory piling; however, it is understood that the only potential sources of construction vibration on the application site would be continuous flight auger (CFA) piling and borehole drilling 5. These are both performed using rotary action drills and are not considered to be driven or vibratory. Measured data provided in BS 5228 for augering and drilling gives ppv levels for a variety of ground types at various distances; these are used to assess on site construction vibration There are no accepted formulae for the prediction of the passage of vibration through ground due to the non-uniform effects of different ground conditions, although some empirical formulae have been proposed for known ground conditions based on previously measured data Due to the large influence local ground conditions have on the transmission of vibration, the predicted vibration ppv values should be treated as estimates. Operational Noise Change in Site Use There is the potential for noise impacts from the operation of the proposed development due to: The use of the new Studio Theatre; Increase in the number of people entering and leaving the theatres/library; and The change in the location of the loading bay The new shared space between The REP and the new library will incorporate a Studio Theatre that would seat approximately 300 people. This would be in addition to the Main Stage (850 people) and The Door (140 people) theatres already on the site. It is understood that all theatres could be used simultaneously. The new Studio Theatre would be fully enclosed in the new building and hence noise breakout through the building façade would be minimal. However, ventilation to the new theatre, is a potential source of noise breakout. Currently there is no information available detailing the ventilation system. In the absence of suitable data, noise limits at ventilation outlets would be set based upon Birmingham City Council criteria for entertainment noise at the nearest residential receptors The number of people visiting the library is expected to increase from 5,000 to 10,000 per day Two external garden terraces are proposed, the City Terrace on the third floor overlooking Centenary Square and the City Garden on the seventh floor which overlooks the Rep Theatre roof and the gardens on Cambridge Street. The City Terrace is intended to provide an outside extension to the library where people can go to read and this area could host small events, the City Garden is intended as a relaxing open green roof space which may be used for education The REP loading bay is currently located on the northern side of the building on Cambridge Street. Noise from the loading bay is generated by articulated lorries loading/unloading equipment and scenery for the theatre. It is understood that noise 15-4

6 from the current use of the loading bay has not been the cause of complaints. The proposed development will relocate this facility to the eastern side of building facing the International Convention Centre (ICC) with a new loading bay provided onto Cambridge Street which will allow deliveries to be made to the rest of the development The loading/unloading of scenery generally happens between 22:00 and 02:00. In order to assess the noise from the loading bay, noise measurements were taken on site on 20 June 2009 between 22:30 and 01:30, during which time an articulated lorry was loaded with scenery within the existing loading bay after reversing in. The measurements have been used to assess the effect of changing the loading bay locations. Operational Noise Fixed Plant Noise from any fixed plant associated with the development such as roof mounted fans or air handling units, may impact on sensitive receptors. Any fixed plant would have to be assessed in accordance with BS This standard is discussed in Appendix The proposals show plant rooms on the: Lower ground floor of The REP (plant enclosed); First floor of the new library (plant enclosed); Roof of The REP (external plant with 3.5 m parapet surround); Eighth floor of the new library (plant enclosed) For the enclosed plant rooms, it is considered that noise breakout through the plant room walls is unlikely to be significant and this has therefore been scoped out of the impact assessment. However ventilation would be provided to the plant rooms, with the potential for noise breakout to impact on residential receptors There is potential for noise impact from external plant on the roof of the development, which will have a direct line of site to residential receptors in the upper levels of the flats (Cambridge Tower) It is currently not known what plant is to be contained within the plant rooms and where ventilation outlets would be on the building; therefore this report provides overall noise limits for any future plant at the nearest residential receptors based on BS 4142 criteria and Birmingham City Council policy. Significance Criteria: Construction Noise The significance of construction noise levels has been assessed using the ABC Method provided in BS (Section E.3.2, Table E.1) 2 as shown in Table

7 Table 15.2 Construction Noise Threshold of Significant Effect Assessment Category and Threshold Value () Threshold Value Period Category A a) Category B b) Category C c) Nighttime (23:00 07:00) Evenings and Weeken ds d) Daytime (07:00 19:00) and Saturday s (07:00 13:00) NOTE 1: A significant effect has been deemed to occur if the total L Aeq noise level, including construction, exceeds the threshold value for the category appropriate to the ambient noise level. NOTE 2: If the ambient noise level exceeds the threshold values given in the table, then a significant effect is deemed to occur if the total noise level for the period increases by more than 3 due to construction activity. NOTE 3: Applies to residential receptors only. a) Category A: Threshold values to use when ambient noise levels (when rounded to the nearest 5 ) are less than these values. b) Category B: Threshold values to use when ambient noise levels (when rounded to the nearest 5 ) are the same as Category A values. c) Category C: Threshold values to use when ambient noise levels (when rounded to the nearest 5 ) are higher than Category A values. d) 19:00 23:00 weekdays, 13:00 23:00 Saturdays, 07:00 23:00 Sundays For the appropriate period (night, evening/weekend, day), the ambient noise level is established and rounded to the nearest 5. The appropriate Threshold Value is then determined. The total noise level (sum of prevailing ambient level and estimated construction noise level) is then compared with this Threshold Value. If the total noise level exceeds the Threshold Value, then a significant effect is deemed to occur The significance of the daytime and night-time construction noise at selected receptors is assessed based on the criteria outlined in Table 15.3 below. The criteria have been developed by Scott Wilson based on a range of current guidance. The method of assessment has been discussed and agreed with Birmingham City Council 7,

8 Table 15.3 Noise Significance Criteria Noise Level Above BS 5228 Threshold Value (A) Significance Criteria <=1 Negligible 1>3 Minor 3>5 Moderate 5>10 Major >10 Severe Significance Criteria: Construction Vibration Building Damage British Standard BS 7385: Part 2: 1993 Evaluation and measurement for vibration in buildings Part 2 9 Guide to damage levels from ground-borne vibration gives guidance on the levels of vibration above which building structures could be damaged. For the purposes of BS 7385, damage is classified as cosmetic (formation of hairline cracks), minor (formation of large cracks) or major (damage to structural elements). Guide values given in the Standard are associated with the threshold of cosmetic damage only, usually in wall and/or ceiling lining materials Limits for primarily transient vibration (from a train, for example) above which cosmetic damage could occur are reproduced exactly below in Table These limits can be used to assess the likelihood of structural damage arising from vibration associated with construction or any permanent new sources of vibration. Table 15.4 Transient Vibration Guide Values for Cosmetic Damage (from BS 7385: Part ) Peak Component Particle Velocity in Frequency Type of Building Range of Predominant Pulse 4 Hz to 15 Hz 15 Hz and above 1 Reinforced or framed structures. Industrial and heavy commercial 50mms -1 at 4 Hz and above 2 buildings Unreinforced or light framed structures Residential or light commercial type buildings 15 mms -1 at 4 Hz increasing to 20 mms -1 at 15 Hz 20 mms -1 at 15 Hz increasing to 50 mms -1 at 40 Hz and above NOTE 1. Values referred to are at the base of the building NOTE 2. For line 2, at frequencies below 4 Hz, a maximum displacement of 0.6 mm (zero to peak) should not be exceeded. Significance Criteria: Construction Vibration Human Annoyance The lower limit of human perception to vibration is of the order of 0.15 mms -1 to 0.3 mms - 1 ppv, in the frequency range 0.1 Hz to 1500 Hz. The human body is not equally sensitive to all frequencies of vibration and weighting curves to reflect the frequency dependency of the body have been developed and are contained within ISO Standards. The weighting gives a good correlation between the measured vibration level and the subjective feeling or impact produced by the vibration. 15-7

9 15.47 The predicted ppv levels are compared to the guidance levels in Table B.1 in BS 5228 (reproduced as Table 15.5), to identify the likelihood of complaint. Table 15.5 Guidance Effects of Vibration for Human Reponses (BS 5228 Part 2: 2009) Vibration Level mms -1 Effect Vibration might be just perceptible in the most sensitive situations for 0.14 most vibration frequencies associated with construction. At lower frequencies, people are less sensitive to vibration 0.3 Vibration might be just perceptible in residential environments It is likely that vibration of this level in residential environments will 1.0 cause complaint, but can be tolerated if prior warning and explanation has been given to residents. Vibration is likely to be intolerable for any more than a brief exposure to 10 this level. Significance Criteria: Operational Noise There is the potential for noise breakout from the Studio Theatre via ventilation ducting to impact on the nearest residential receptors. Birmingham City Council noise and vibration policy 10 states that noise breakout from noise sources of a non-industrial nature need to be assessed using the WHO Guidelines 11. Correspondence with Birmingham City Council 8 has confirmed that noise breakout from the new Studio Theatre should not exceed the noise limits set in the WHO Guidelines for outside of bedroom windows as shown in Table Table 15.6 WHO Guidelines for Night Time Noise Specific Environment Critical Health Effect(s) L Aeq [] L AFmax, [] Outside Sleep disturbance, window open (outdoor bedrooms* values), evenings ( ) - 60* Outside Sleep disturbance, window open (outdoor bedrooms values), night-time (23:00-07:00) * additional criteria applied by Birmingham City Council The noise impact at the nearest noise sensitive receptors due to increases in visitors to the site or change in the location of the loading bay is assessed using the significance criteria in Table 15.7 and agreed in principle with Birmingham City Council 7. Table 15.7 Significance of Changes in Noise Level at Receptor Locations Change in Noise Level at Receptor Location (L Aeq ) Significance Decrease of 3 or more Perceptible decrease Decrease of less than 3 No significant change No change No significant change Increase of less than 3 No significant change Increase of 3 to < 5 Low increase Increase of 5 to <10 Medium increase Increase of 10 to 15 High increase Increase of > 15 Very High increase 15-8

10 Significance Criteria: Operational Noise Fixed Plant BS 4142 suggests that a rating level excess of up to 5 (A) above the ambient background noise level at the receptor is of marginal significance and if the rating level due to the noise source exceeds the ambient background noise level by more than 10 (A) then the indication is that complaints would be likely. If the rating level of the noise source is more than 10 (A) below the ambient background noise level this is a positive indication that complaints are unlikely The Birmingham City Council noise and vibration policy describes a two step approach to limiting plant noise: Step 1: Design the site to achieve a rating level 10 (A) below the existing background level at noise-sensitive premises; Step 2: Where a rating level of 10 (A) below background is not achievable then this must be demonstrated, and the achievable level identified Birmingham City Council has confirmed that they have no specific noise limits for fixed plant affecting commercial premises such as Baskerville House 7. However, the impact of any plant noise on the nearest receptors should be minimised. Existing Noise Levels Summarised noise measurement data for the long and short-term measurements are provided in Table 15.8 and 15.9 respectively. The full long-term noise monitoring data are shown graphically in Figure The long-term noise measurements show that L Aeq,8hour noise levels at Baskerville House overlooking the development site remained above 55 and the L Aeq,16hour reached a maximum of 63. Averaging over the full monitoring period, the day time L Aeq,16hour was 60 and the night time L Aeq,8hour was 58, showing only a small reduction in noise levels at night Local and distant road traffic dominated at all locations, with occasional aircraft and police sirens also contributing to the noise climate. Noise levels were relatively constant. All short-term measurements were between L Aeq,T. Table 15.8 Summary of Long-Term Noise Monitoring Data for Baskerville House(LT1) Daytime (07:00-23:00) Night time (23:00-07:00) Day (May 2009) L Aeq,T * L Amax,fast + L A90,T L Aeq,T * L Amax,fast + L A90,T Saturday 2 nd / rd Sunday Sunday 3 rd / th Monday Monday 4 th / th Tuesday Tuesday 5 th / th Wednesday

11 Daytime (07:00-23:00) Night time (23:00-07:00) Day (May 2009) L Aeq,T * L Amax,fast + L A90,T L Aeq,T * L Amax,fast + L A90,T Wednesday 6 th / th Thursday Thursday 7 th / th Friday Friday 8 th / th Saturday Saturday 9 th / th Sunday Sunday 10 th / th Monday Monday 11 th / th Tuesday Average * logarithmic average of L Aeq,15min data + arithmetic average of L A90,15min data Figure 15.2: Monitoring Results for Baskerville House 6th Floor Lp (A) LAeq LA90 LAmax :00 23:00 05:00 Saturday 2nd May 2009 Sunday 3rd May :00 17:00 23:00 05:00 11:00 Monday 4th May :00 23:00 05:00 11:00 17:00 Tuesday 5th May :00 05:00 11:00 17:00 23:00 Wednesday 6th May :00 11:00 17:00 Time Thursday 7th May :00 05:00 11:00 17:00 23:00 Table 15.9 Summary of Short-Term Noise Monitoring Friday 8th May :00 11:00 17:00 23:00 05:00 Saturday 9th May :00 17:00 23:00 05:00 11:00 Sunday 10th May :00 23:00 05:00 Monday 11th May 2009 Location Date Time Duration L Aeq,T L Amax,fast L A90,T City Centre Gardens (ST1) 01/05/09 12:00 15 min :20 35 min Base of Cambridge Tower (ST2) 12/05/09 09:23 27 min Roof Level, Cambridge Tower (ST3) * logarithmic average of L Aeq,15min data + arithmetic average of L A90,15min data 01/05/09 12:23 32 min

12 15.56 No long-term monitoring was carried out at Cambridge Tower due to the lack of any secure locations to leave equipment. Short-term daytime noise levels measured at Cambridge Tower have been compared with the levels measured during a similar time period at the long-term monitoring location at Baskerville House. The results are shown in Table Table Comparison of Measured Noise Data Location Date Time Period L Aeq,T L A90,T Baskerville House (LT1) 12:15-13: /05/09 Roof Level, Cambridge Tower (ST3) 12:23-12: It can be seen that there was difference of 4 between the L Aeq,T at each location, and a difference of 5 between the L A90,T values measured. It is assumed that a similar difference in noise levels occurs between the two locations at night. Therefore the night time L A90,8hour at Cambridge House is assumed to be An assessment of existing ambient noise levels, in which an L A90,15min of 46.1 was recorded during the late evening in front of Cambridge House, was carried out by the design team in November This corresponds well when compared with the estimated night time level of 46 L A90,8hour. Construction Noise Impact Assessment Predictions have been carried out for Baskerville House, Cambridge/Crescent Tower, and the International Convention Centre, as well as the former Municipal Bank and Central House. Construction noise does not need to be assessed for The REP, as the venue would be closed during the proposed works Birmingham City Council have advised that they are most concerned with the impact of construction noise on residential receptors and not commercial premises, providing best practice methods are used to minimise noise impact The following construction activities are anticipated 5 : 1. a) initial archaeological works and b) second stage archaeological works; 2. boreholes for ground source heat pumps (GSHP); 3. initial excavation; 4. initial piling; 5. demolition of existing REP extension; 6. excavation of deep basement; 7. piling within basement; 8. superstructure erection; 9. demolition at the front and rear of The REP; 15-11

13 10. excavation of basement at front and rear of The REP; and 11. structure erection These are followed by a Fit out phase that is predominantly internal and therefore only minimal noise impact is likely It is proposed that construction works would only occur between 07:00-18:00 Monday- Friday (not including Bank Holidays) and 07:00-13:00 on Saturdays Ambient noise levels measured at Baskerville House during the proposed construction times were 61 L Aeq,T. Short-term daytime measurements made at the top and bottom of Cambridge Tower as well as in the City Centre Gardens were L Aeq,T. This means that all of the nearest receptors are considered to be Category A, with a threshold level of 65 L Aeq,T The results of the assessment are shown in Table Construction noise levels at the nearest residential properties during the majority of activities are predicted to be of negligible significance. The threshold value is only marginally exceeded during initial piling works and during demolition to the rear of The REP Baskerville House which is adjacent and overlooking the application site, would experience a temporary increase in noise levels of up to 9 L Aeq,1h under worst case conditions that would be likely to extend for up to 11 weeks as a result of piling, excavation and demolition. For the majority of the time, noise levels would be significantly lower The proposals include a 2.8m site hoarding around the entire site. Assuming this is correctly erected with no gaps or holes between or underneath the panels, this can provide up to 10 reduction of the noise levels at the nearest noise sensitive receptors providing the hoarding blocks line of sight to the plant

14 1a 1b 2 Birmingham City Council Table Significance of Impact during Daytime Construction Works at Baskerville House Receptor (R1) Activity Initial archaeological works Second stage archaeological works Boreholes for GSHP Predicted Construction Free Field Noise L Aeq,1h () Baskerville House (Minimum distance 20m) Ambient + Level Construction above Significance Noise L Aeq,1h Threshold Predicted Construction Free Field Noise L Aeq,1h () Cambridge Tower / Crescent Tower (Minimum distance 80m) Ambient + Level Construction above Significance Noise L Aeq,1h Threshold Predicted Construction Free Field Noise L Aeq,1h () International Conference Centre (Minimum distance 11m) Ambient + Level Construction above Significance Noise L Aeq,1h Threshold Predicted Construction Free Field Noise L Aeq,1h () Bank and Central House (Minimum distance 50m) Ambient + Level Construction above Significance Noise L Aeq,1h Threshold 65 0 Negligible 57-8 Negligible 56-9 Negligible 62-3 Negligible 65 0 Negligible 57-8 Negligible 56-9 Negligible 62-3 Negligible Major 61-4 Negligible Major Minor 3 Initial excavation Major 64-1 Negligible Negligible Minor 4 Initial piling Major Minor Moderate Moderate Demolition of existing REP extension Excavation of deep basement Piling within basement Superstructure erection Demolition at front and rear of The REP Excavation of basement at front and rear of The REP Structure erection Major 64-1 Negligible Minor Minor Major 64-1 Negligible Negligible Negligible Major 65 0 Negligible Minor Minor Minor 59-6 Negligible 60-5 Negligible 63-2 Negligible Minor 62-3 Negligible Major Negligible Moderate Negligible Major Minor Negligible 59-6 Negligible 63-2 Negligible 63-2 Negligible 15-13

15 Construction Noise Haul Road It is proposed that the haul road operates as a one-way system which, starting at the site, goes west along Cambridge Street, King Edwards Road and Summer Hill Street. HGVs can then turn left or right onto Sand Pits Parade, with entrance to the site via Paradise Circus Queensway and left into Cambridge Street. Predictions have been undertaken at the receptors detailed in Table Table 15.12: Predicted Noise Levels from Construction Haul Road During Daytime Hours Receptor Minimum Distance to Haul Road (m) Predicted L Aeq,1h (Free-Field) from Construction HGVs () Measured baseline noise level L Aeq () Baskerville House Cambridge Tower Crescent Tower Galton/Norton Tower Vincent House Acorn Grove Monitored daytime noise levels at Baskerville House and Cambridge/Crescent Tower during the baseline monitoring (see Table 15.2 and 15.3) are higher than that of the forecast noise from the HGV traffic. It is considered that noise from haul road traffic would not cause any significant impact at these three receptors, as well as Galton/Norton Towers which are closer to Cambridge Street Road traffic on Cambridge Street/King Edwards Road/Summer Hill Street and Sand Pits Parade is the main noise source affecting Vincent House and 29 Acorn Grove. Given existing noise levels measured at other locations at greater distances from these roads, it is considered that noise from haul road traffic would not cause any significant impact. Construction Vibration - Assessment Building Damage Table details the nearest vibration sensitive receptors to the construction works, with the minimum distance to piling and bore hole drilling locations It is understood that continuous flight auger (CFA) piling is proposed on the site 5. BS 5228 advises that the level of vibration generated by this method of piling is minimal The highest measured ppv is 0.54 mms -1 at 5m, with levels at 20-30m generally below 0.1 mms -1. These are significantly below the 5 mms -1 limit at which even cosmetic building damage becomes likely. Therefore, no significant effects due to vibration from piling are predicted

16 15.74 Two boreholes are to be drilled at the site for the purpose of ground source heat pumps. Data from BS 5228 show vibration levels caused by drilling are comparable with that generated by the augering process used in CFA piling and therefore not significant Table Nearest Vibration Sensitive Receptors Receptor Minimum Distance to CFA Piling/Bore hole Drilling (m) Baskerville House (Municipal Offices) 20/35 Cambridge Tower 80/112 Crescent Tower 96/83 International Conference Centre 100/29 Bank and Central House 50/63 The REP (section not being demolished) Hall of Memory (War Memorial) 15/11 33/23 Underground railway line 22/42 Human Annoyance Assuming vibration levels remain inside the range of values expected, vibration due to piling and drilling is likely to be significantly below the just perceptible criteria for residential buildings at the nearest residential properties 80m away At Baskerville House under worst case conditions (activities occurring at the minimum distance), vibration due to piling and drilling may be just perceptible. However, piling at this distance would only occur for a short proportion of the 11 week piling period and is therefore unlikely to cause annoyance. Operational Noise Change in Site Use New Studio Theatre The Studio Theatre has no room surfaces that form any part of the external façade, and therefore the only significant noise breakout would be via ventilation outlets. As the location of ventilation outlets has not been finalised, forecasts have assumed a single outlet at a distance to the nearest residential receptor 80m, with direct line of sight to Cambridge Tower from the vent outlet, ignoring any ground or barrier effects A maximum break out sound power level of 91 L WAeq and 106 L WAmax,fast would ensure that WHO limits are met at the nearest receptors (see Table 15.14). These levels would be set as criteria in the selection and design of the theatre ventilation system

17 Table 15.14: Maximum Noise Breakout for Session Theatre Ventilation WHO L Distance Attenuation Aeq Maximum break L WAmax,fast Maximum break limit at out L to due to Aeq sound limit at out sound power residential power level of residential L Cambridge distance WAmax,fast noise receptors outlet receptors level Tower (m) Any additional outlets would reduce the maximum permitted break out noise level. Should all of the outlets be positioned facing away from the residential receptors then the maximum breakout noise levels could be increased. Visitors to the Site Should all three theatres be used simultaneously and at full capacity, the number of people visiting the site for performances would increase by 300 from 900 to This represents a 1 change in noise levels from theatre patrons, which does not represent a significant change. It should also be noted that other sources of noise in Centenary Square (other people not related to the theatre, traffic noise, etc.) would reduce the magnitude of this change further The number of people visiting the library is expected to increase from 5,000 to 10,000 during daytime operating hours. The current library is situated close to the new site and a doubling of visitors could be expected to result in a maximum increase of 3 in noise from this source. However, the existence of other noise sources would mean that the actual increase in noise levels is likely to be less than this, and the change would occur gradually as visitor numbers increase. Birmingham City Council have advised that they do not consider the impact of increased numbers of visitors to the site to be significant. 7, The use of the external terraces on the third and seventh floor are unlikely to generate significant levels of noise due to their proposed use as quiet, relaxing spaces and should not be considered an issue. The third floor terrace may hold small events for which any entertainment noise, i.e. amplified music, will need to be controlled to meet the limits set out in Table Loading Bay Measurements of L Aeq,1min and L Amax,fast were made whilst scenery was loaded into an articulated lorry which had reversed into the existing loading bay on Cambridge Street. These measurements were taken at Cambridge Street facing the loading bay (Location 1) and adjacent to the loading bay on The REP side of Cambridge Street (Location 2). Results are shown in Table Subjectively, noise from the loading activities was barely audible above the traffic noise, and only occasional bangs were heard due to items being dropped into the HGV. As the loading occurred within the loading bay, with the articulated lorry facing out, the noise was largely contained within the loading bay The L Aeq,1min data have been logarithmically averaged to give the resultant L Aeq,T. The L Aeq,1min noise levels when loading activity could be heard are generally lower than the 15-16

18 L Aeq,T levels when no loading activity could be heard and it does not influence the overall L Aeq which is dominated by the fluctuating noise level of passing road traffic The L Amax,fast level of 83 is due to loading bay activities. Allowing for the decay in level over the distance of 80m to the nearest receptor a reduction of 46 would be expected. This would result in a level of 37 L Amax,fast outside the nearest residential receptors which is well below the night time limit defined in the WHO guidelines. Table Loading Bay Measurements Location Time Description of noise L Aeq,T L Amax,fast No loading activity audible 1 22:30-23: :21-23: :00-00:46 Road traffic noise dominant, police sirens Road traffic noise dominant, aircraft noise, noise from revellers Road traffic noise dominant, noise from revellers, loud music from passing cars :59-01:15 Road traffic noise dominant Loading activity audible 1 23:01-23:02 Traffic noise minimal, loading audible :13-23:14 Loading audible :18-23: :20-23:21 Includes two loud bangs from the loading activities Includes two loud bangs from the loading activities :48-00: :51-00: Loading noise audible 2 00:58-00: :17-01: The new loading bay for scenery would be located to the side of the building further from residential receptors with loading taking place inside the building. The existing loading bay would be replaced with a new loading bay onto Cambridge Street which will be for deliveries to the rest of the development; this bay is unlikely to be used at night There would not be any significant noise impact from the loading bays for the nearest residential receptors

19 Operational Noise Fixed Plant Noise from fixed plant has the potential to adversely impact on the nearest receptors due to breakout through the building façade, penetrations in the façade for ventilation plant and noise from external plant Noise from fixed plant should be adequately controlled using appropriate mitigation.. Recommended noise limits at the nearest receptors for all fixed plant noise are provided in Table Cumulative Effects No significant operational noise impacts from the proposed development are expected, and the cumulative impact in combination with other developments proposed in the area is considered to be negligible If construction of the proposed development coincides with the construction of other committed developments in the immediate vicinity, the noise from multiple construction sites may have a cumulative effect at some commercial premises which are close to all construction sites (such as Baskerville House) The likely cumulative noise effect of multiple construction sites would be one of increasing the duration of construction noise affecting these commercial premises, rather than one of increased noise levels. Mitigation Measures Construction Noise The proposal includes for a 2.8m timber hoarding to be erected around the entire site throughout the construction works. This would provide between 5-10 attenuation for any receptors at ground floor height or where line of sight is broken between source and receptor It is understood that the 07:00 site start time would be under review should any disturbance be seen to be caused to local residents Although construction noise levels from the proposed works are predicted to fall below the 65 L Aeq,1h (free-field) daytime limit at the selected receptors during most construction activities, the contractor would follow best practicable means to reduce the noise impact upon the local community, especially during any night-time working, including the following: All construction plant and equipment would comply with EU noise emission limits. Proper use of plant with respect to minimising noise emissions and regular maintenance. All vehicles and mechanical plant used for the purpose of the works 15-18

20 should be fitted with effective exhaust silencers and should be maintained in good efficient working order. Selection of inherently quiet plant where appropriate. All major compressors would be sound reduced models fitted with properly lined and sealed acoustic covers which would be kept closed whenever the machines are in use and all ancillary pneumatic percussive tools should be fitted with mufflers or silencers of the type recommended by the manufacturers. Machines in intermittent use would be shut down in the intervening periods between work or throttled down to a minimum. For specific events, e.g. erection of cranes or delivery of certain materials, which are likely to occur outside of the agreed working hours, would be agreed in advance with the Environmental Health Officer. All ancillary plant such as generators, compressors and pumps would be positioned so as to cause minimum noise disturbance, i.e. where possible, close to site hoardings. Construction contractors would be obliged to adhere to the codes of practice for construction working and piling given in BS 5228 and the guidance given therein minimising noise emissions from the site. Reference would be made to the Building Research Establishment, BRE Pollution Control guidelines, Parts Site mobile plant items are often fitted with reversing alarms to act as a safety feature where the driver s visibility is restricted. Noise from vehicles with standard bleeper reversing alarms may give rise to complaint. For Health and Safety reasons vehicles on site will be required to use reversing alarms; however vehicle warning horns would not be used unless in an emergency To reduce any potential noise annoyance, it is advisable that the residents of Cambridge Tower and Crescent Tower, along with the owners of Baskerville House, are informed by letter of the proposed works and anticipated durations and are provided with details at a site contact (accessible at all times during operational hours) in advance. This would also inform them that noise levels may be high for individual, short periods of work, but that such periods would remain as short as possible. Construction Vibration No mitigation measures would be required for the mounted auger piling and bore hole activities Operational Noise Change in Site Use While no specific mitigation is required from the change in site use, detailed design would ensure that noise breakout through any ventilation for the Studio Theatre does not exceed sound power levels of 91 L WAeq and 106 L WAmax,fast

21 Operational Noise Fixed Plant With appropriate detailed design, the noise limit needed to meet the Birmingham City Council BS 4142 assessment criterion can be met for all new plant (see Table 15.16). Table BS 4142 Noise Limits at Nearest Residential Receptors Details Measured Background Noise Level (L A90,5min ) Maximum L Ar,T for fixed plant (10 below background)* Cambridge/Crescent Tower Baskerville House Day Night Day * Birmingham City Council criteria including any penalty for acoustic characteristics For commercial premises, use of a rating level 5 above the background noise level in accordance with BS4142 is considered appropriate. Accounting for the sound attenuation of the building façade, this should result in acceptable internal noise levels within the office spaces. No limits are required for night time noise levels at these commercial properties Residual Effects Assuming vibration levels remain inside the range of values expected, vibration due to piling and drilling are likely to be significantly below the just perceptible criteria for residential buildings from BS 7385 at the nearest residential properties 80m away A temporary short-term noise impact at Baskerville House and other commercial receptors where site hoardings do not block line of sight to construction activities, is not considered to be a significant adverse impact There is unlikely to be any significant noise impact provided that appropriate mitigation is included in the detailed design of the ventilation system to the Studio Theatre and plant rooms, with appropriate noise limits on any external plant

22 References 1 British Standard BS 7445: 1991 Description and Measurement of Environmental Noise. British Standards Institution 2 BS 5228: 2009 Code of Practice for Noise and Vibration on Construction and Open Sites, Part 1: Noise. British Standards Institute. 3 Carillion Library of Birmingham Predicted Traffic Movements. 4 Control of Vibration and Noise During Piling British Steel, Construction Schedule and Plant Notes from Meeting with Carillion (Construction Contractor) 31st March BS 4142:1997 A Method for Rating Industrial Noise in Mixed Residential and Industrial Areas British Standards Institute. 7 Meeting between Scott Wilson and Birmingham City Council regarding aspects of Environmental Impact Assessment for Library of Birmingham, 6th April Telephone correspondence between Nick Massey (Birmingham City Council EHO) and Andrew Nash 8th July BS 7385: 1993 Evaluation and measurement for vibration in buildings Part 2: Guide to damage levels from groundborne vibration. British Standards Institution 10 BCC Environmental and Consumer Services Department Environmental Protection Unit Planning Guidance Note 1 Noise and Vibration March WHO Guidelines for Community Noise Library of Birmingham integrated with the rep Stage C Submission, Mecanoo 9th April correspondence from Alan Wood of Carillion Plc to Kerry Daykin Scott Wilson, 3rd July

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26 Appendix 15 Noise and Vibration Appendix 15.1 Noise and Vibration Terminology Noise Perception and Terminology Between the quietest audible sound and the loudest tolerable sound, there is a million to one ratio in sound pressure (measured in pascals, Pa). Because of this wide range, a noise level scale based on logarithms is used in noise measurement called the decibel () scale. Audibility of sound covers a range of approximately 0 to 140. The human ear system does not respond uniformly to sound across the detectable frequency range and consequently instrumentation used to measure noise is weighted to represent the performance of the ear. This is known as the 'A weighting' and annotated as (A). Table lists the sound pressure level in (A) for common situations. Table 7.2.1: Noise Levels for Common Situations Approximate Sound Pressure Levels (A) Example 0 Threshold of hearing 30 Rural area at night 50 Quiet office, no machinery 80 General factory noise level 100 Pneumatic drill 140 Threshold of pain The noise level at a measurement point is rarely steady, even in rural areas, and varies over a range dependent upon the effects of local noise sources. Close to a busy motorway, the noise level may vary over a range of 5 (A), whereas in a suburban area this may increase up to 40 (A) and more due to the multitude of noise sources in such areas (cars, dogs, aircraft etc.) and their variable operation. Furthermore, the range of night-time noise levels will often be smaller and the levels significantly reduced compared to daytime levels. When considering environmental noise, it is necessary to consider how to quantify the existing noise (the ambient noise) to account for these second to second variations. A parameter that is widely accepted as reflecting human perception of the ambient noise is the background noise level, L A90. This is the noise level exceeded for 90% of the measurement period and generally reflects the noise level in the lulls between individual noise events. Over a one-hour period, the L A90 will be the noise level exceeded for 54 minutes. The equivalent continuous A-weighted sound pressure level, L Aeq, is the single number that represents the total sound energy measured over that period. L Aeq is the sound level of a notionally steady sound having 15A-1

27 Appendix 15 Noise and Vibration the same energy as a fluctuating sound over a specified measurement period T (i.e L Aeq,T ). It is commonly used to express the energy level from individual sources that vary in level over their operational cycle. Even though sounds appear fairly steady to the human ear they are seldom if ever steady in level. To accommodate this factor, sound level meters (SLMs) are generally provided with at least two meter responses or exponential averaging circuits. Fast meter response has a time constant of 1/8th of a second (125ms) and approximates the integration time of human hearing. The slow time response (time constant = 1 second) is intended to obtain an approximate average value of rapidly fluctuating levels from simple meter readings. The maximum level, L Amax,fast, is the highest A-weighted sound pressure level measured during a noise event (30 seconds, 5 minutes etc.),, on a fast sound level meter response setting. It is sometimes used to assess the likelihood of sleep disturbance. Most environmental noise measurements and assessments are undertaken for free-field, away from any existing reflecting surfaces (other than the ground). However, it is sometimes necessary to consider noise levels immediately external to a façade when considering the impact on residents inside properties and this normally requires the addition of up to 3 (A) to the predicted (or measured) free-field level due to noise reflection from the façade. The assessment of road traffic noise, for example, is based on a predicted (or measured) façade noise level (using the L A10 statistical parameter). Human subjects, under laboratory conditions, are generally only capable of noticing changes in steady levels of no less than 3 (A). It is generally accepted that a change of 10 (A) in an overall, steady noise level is perceived to the human ear as a doubling (or halving) of the noise level. (These findings do not necessarily apply to transient, non-steady or intermittent noise sources). Sound power is the rate per unit time at which airborne sound energy is radiated by a source. It is expressed it watts (W). Sound power level or acoustic power level is a logarithmic measure of the sound power in comparison to the reference level of 1 pw (picowatt). The sound power level is given the letter "L w " or SWL and is measured in. It is not the same thing as sound pressure (L p ). Any L p value is dependent of the distance from the noise source and the environment in which it was measured. L w values are preferred for noise prediction purposed as their value is independent of distance or environment. There are recognised formulas for converting L w to L p. A-weighted sound power levels are usually denoted L wa () or sometimes L w (A) or SWL (A). Perception and Terminology Vibration When an object is in contact with a vibrating surface, it is displaced about its reference (stationary) position. Displacement (in mm) is therefore one parameter that can be used to describe the magnitude of a vibration. For sinusoidal signals, displacement, velocity (ms -1 ) and acceleration (ms -2 ) amplitudes are related mathematically by a function of frequency and time. If phase is neglected (as is always the case when making time-average measurements), then the velocity can be obtained by dividing the acceleration signal by a factor proportional to frequency (measured in Hertz, Hz) and the displacement can then be obtained by dividing the acceleration signal by a factor proportional to the square of frequency. Modern electronic integrating meters are capable of providing a wide range of measurement parameters during any single vibration measurement. For a complex acceleration signal that gives rise to a complicated time history, several additional quantities can be used to describe the vibration: 15A-2