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					                                       “Workshop_input parameters lists_31_3_2009.doc”
This document contains a table of input parameters / input values typically used in noise mapping assessment and was presented and discussed
during the Workshop on “Noise mapping according to the 2002/49/EC – Target quality and input values requirements” jointly organised
by DG ENV, DG JRC and EEA on 16-17 March 2009 in Ispra. The scope of this table is to retrieve suggestions, experience gained, values
concerning:
                  Accuracy of calculated levels against uncertainty of parameters;
                  General remarks (i.e., easiness to retrieve, problems/lessons from 1st round noise mapping);
                  Inclusion/exclusion from mandatory requirements of the 2nd round mapping;
                  Status and/or needs for standardization of the input value format;
                  Information on numerical studies performed to quantify the type A uncertainty.


Description of    Accuracy         Easiness to find/retrieve/use this parameter;             Inclusion or exclusion of     Are there any      Is it possible
the               of                                                                         this parameter from the       standards to use   to associate
parameter/input   calculated       Problems encountered during the first round of            mandatory set of input        for acquiring      type A
value.            level at a       noise mapping;                                            values for the 2nd round      this parameter?    uncertainty to
                  single point                                                               of noise mapping because                         this input
                  if this and      Lessons learned concerning the use of this                it is considered negligible   If not, is there a parameter?
                  only this        parameter during the first round of noise                 or inappropriate.             need of
                  specific         mapping;                                                                                standardisation? Please report
                  parameter                                                                                                                   any
                  is                                                                                                       Does it match      numerical
                  uncertain.                                                                                               the                study
                                                                                                                                  INSPIRE performed to
                                                                                                                           Directive?         quantify this
                                                                                                                                              uncertainty.


                                                GENERAL PARAMETERS
1ST
GENERATION
MODEL OR 2ND      For aircrafts,   Discussion (short) on the overall views on the adoption   Method should be mandatory
GENERATION        1 dB 1st         of mixed up source-propagation methods (1st generation)
MODEL             generation       or on sound power definition + separated propagation
              calculation methods (2nd generation methods).
No info on
accuracy of   2nd generation model preferred. Some discussion about
the 2nd       whether Common Method should be “lowest common
generation    denominator” to ensure all MS capable of working with
              it, or whether it should be “best of breed” to support best
              practice across EC and provide for level of aspiration.

              End point of discussion came to “fit for purpose”
              although the definition of this was not explored in detail.
              Across the remainder of the workshop session I would
              conclude that a means of defining “fit for purpose”
              would be:

                 (1) Support EU level policy aspects
                     - (based upon source noise legislation) including
                     tyre noise, vehicle pass by noise, road surfaces,
                     rail vehicle interoperability, aircraft fleet
                     restrictions etc.
                     - The method needs to be able to support these
                     policy areas by being able to use such data as
                     inputs, either to reflect the current situation, or to
                     run "what if" scenarios to help formulate policy
                     change proposals, or assess policy change
                     impact.
                 (2) Supports MS level policy aspects
                     - vehicle restrictions
                     - tyre restrictions or special types
                     - promotion of electric / hybrid vehicles
                     - promotion of vehicle fleet change through
                     financial incentives to scrap older cars
                     - action plan policies etc
                 (3) Local Action Plan policy aspects
                     - such as the ideas within the Silence handbook
                     - road surface changes
                     - absorbent barriers
                     - photovoltaic barriers
                     - rail grinding
                     - rail vehicle brake changes
                     - switch from diesel to electric rail
                     - switch to electric/hybrid cars
                               - low emission zones etc

                        From the aircraft point of view, the second generation
                        might be closer to "acoustical point of view" but both
                        have accuracy and they might both be detailed, so, is
                        there a need to change?


                        IMO the method needs to provide source definitions,
                        propagation methods and receptor assessments which
                        enable policy options or action plan options to be
                        investigated in what if scenarios, as well as providing a
                        means of delivering population exposure statistics based
                        upon strategic noise maps

                        By undertaking a review of the above factors a definition
                        of “fit for purpose” may be developed, and this can then
                        be used alongside the technical review of the available
                        methods to provide supporting evidence for the selection
                        of a Common Method.
Definition of area to
be mapped
                        Area around major road and rail sources should be           Mandatory guidance – use to
                        determined using methods in GPG Toolkit 1 or Imagine        be documented
                        WP1

                        Area around major airports to be mapped typically
                        assessed using 50 dB Lden contour or 45 dB Lnight
                        contour

                        Area of agglomeration to be mapped currently
                        determined either at MS or competent authority level.
                        This leads to large variation between MS, and even
                        within MS. These variations introduce bias into the
                        comparison of exposed areas, number of dwellings and
                        even no of people exposed. Can also significantly alter
                        the way quiet areas within agglomerations are handled
                        (edge of urban area open spaces may be omitted from
                        agglomeration definition).
                        There was much discussion on agglomeration definition,
                        but little agreement. There is probably a need to
                  synchronise AQ and Noise agglomeration definitions,
                  whilst some form of guidance is required to reduce
                  variance between MS (if this guidance already exists at
                  EC level it should be referenced and its use made
                  mandatory)
                  The definition of agglomerations probably needs to go
                  back to MS for review in light of the findings of the
                  review of the activities under the first round.

                  For aircraft noise, the definition of the area varies
                  depending on the levels someone is looking at.

Relevant year -
emission
                  Should be notional year from Jan 1st to 31st Dec of year    Mandatory – reporting of
                  prior to reporting deadline e.g. 2012 reports should be     factoring to be mandatory
                  for Jan 1st 2011 to 31st Dec 2011. As recommended in
                  GPGv2.

                  It should be accepted that data may be older, but should
                  be factored/scaled to provide best estimated datasets for
                  assessment year – however ALL factoring/scaling should
                  be documented and reported. Typically these will be
                  with regard to population data (census may be on a 10
                  year repeating cycle) and traffic flow data (which may
                  be published several years in arrears)

                  END says data must be no more than 3 years old, but not
                  clear what this means (e.g. is it acceptable to use data
                  older than 3 years, but factored up to present?). Also,
                  END not clear what relevant year is. A. Bloomfield
                  END Review to consider both (see WG AEN paper on
                  unclear/missing provisions). A. Bloomfield.

                  For aircraft mapping, relevant year, average year are
                  terms that are sometimes confusing, clarification is
                  needed before this can be judged.
Average year-
meteorological
                 3-10 dB      Arguably meteorology is not relevant for urban               Mandatory                                         Yes it is
                 (Industry)   agglomerations due to lack of knowledge regarding its        with defaults set out in                          possible to
                              effect in city noise mapping it is generally recommended     guidance should data be                           make for
                 3 dB         to ignore it – as noise is a short distance pollutant in     missing                                           industry
                 (aircraft)   cities (unlike AQ) there is not real long distance           - and good resolution
                              propagation                                                  between day, evening night

                              For assessment of major sources meteorological data is
                              relevant, was regarded as being widely available in
                              appropriate detail, and should be included

                              Relevant year, average year are terms that are sometimes
                              confusing, clarification is needed before this can be
                              judged
                              To be linked to the options given in the calculation
                              method (Industry)

                              Average year should well be obtained depending on the
                              month. Consider modes of operations e.g. (N-S E-W
                              configurations). Do we give one average or the worst
                              case?

                              See also below under meteorological data (G.
                              DUTILLEUX)

Number of
reflections
                              Ground roll (ground operation) should be considered as       Mandatory                    Not standardised,    (For aircraft an
                              industrial noise and 1-2 reflections are considered.                                      but should be, to    analyses was
                                                                                                                        understand what is   performed…
                              (Some existing methods do not allow for any choice in                                     done.                see Germany
                              this) A. Bloomfield                                                                                            study)

                              Minimum requirement 1st reflection (Babisch)

                              In urban areas a high number of refections is desirable to
                              get close to the real levels but convergence may be an
                              issue.in ray-tracing. A default value of 3 works in most
                              cases. (G. DUTILLEUX)
                                   (S. Shilton): 1st order as a minimum, 3rd order as a
                                   practical maximum for strategic mapping (provides for
                                   courtyards etc without excessive computation load)

Digital terrain
model
                  Depending        Data was generally available to provide the basis of a       Mandatory
                  on terrain,      digital terrain model, however variability was substantial
                  up to 7 dB in    as there are many options available.                         Guidance should be produced
                  the case of                                                                   on means of developing
                  aircraft noise   Z data needs to be more accurate than X,Y data, but is       terrain model
                                   much less readily available, and can be costly to acquire.
                                                                                                Documentation of approach
                                   There are probably 3 main categories of source input         to be mandatory
                                   data:

                                      (1) point datasets such as low resolution “strategic”
                                          ground models which may be 50m or 100m grid
                                          spacing, or high resolution datasets from
                                          LiDAR/laser scans or aerial radar surveys with
                                          grid spacing of 5cm, 10cm or 20cm not
                                          uncommon
                                          - all point datasets must be post processed to
                                          produce equal height contour lines – the accuracy
                                          and resolution of them being determined by the
                                          quality of the source data and the processing
                                          undertaken
                                          - most frequently available from commercial data
                                          suppliers, and can therefore be costly
                                          - most often captured for flood plain analysis,
                                          inherently totally different set of requirements
                                          from noise mapping
                                      (2) Equal height contour datasets, either derived
                                          from survey such as in 1 above, or from
                                          interpretation of aerial photography. May be at
                                          10m, 5m, 2m or 1m vertical height interval,
                                          horizontal resolution dependent upon source of
                                          dataset
                                          - may provide acceptable base terrain model
                                          depending upon accuracy and resolution of base
                           datasets, however often needs processing to
                           remove conflicts with noise model requirements
                           - frequently available from national mapping
                           agencies
                           - currency, resolution and accuracy vary widely
                           between assessment areas and MS
                       (3) 3D breakline datasets, normally produced from
                           interpretation of 3D aerial photography
                           - probably the best datasets for noise modelling,
                           as screen edges and barriers in the terrain are
                           well defined, and slopes can be efficiently
                           modelled
                           - may require processing for best fit to noise
                           model requirements
                           - not commonly available from national mapping
                           agencies
                           - may require specific data capture project

                    The accuracy and resolution of data in the vicinity of the
                    noise sources in more important than that of terrain data
                    further away or at great distance, particularly with major
                    sources. If option 3 is considered as best available
                    dataset, there is often a best practical terrain dataset
                    which is a combination of type 2 contour lines with a
                    detailed breakline model in the vicinity of the noise
                    sources which may be captured by 3D photo
                    interpretation, and can pick produce a 3D breakline
                    model including cuttings, embankments, barriers,
                    buildings etc within, say, 50m of the road/railway line.

Digital buildings
model
                    2D plan data on building footprints generally available      Mandatory

                    Needed for aircraft on the runway – or at low altitudes

Ground
type/impedance
                    Current methodologies mainly work with either ground         No
                    absorption or barrier attenuation. As there are few un-
                    screened propagation paths in many strategic noise           Documentation of approach
                   maps, influence of ground cover is minimal, and in           to be mandatory
                   which case CORINE is generally of sufficient detail.

                   Impact of data resolution would have to be investigated
                   with any proposed Common Method to confirm whether
                   this approach remains valid.

                   The measurement of surface impedance is not realistic in
                   the framework of strategic noise mapping. 2 general
                   purpose values (absorbing or reflecting ground) are more
                   realistic. (G. DUTILLEUX)

                   Needed for aircraft on the runway – or at low altitudes


Building Usage

                   Data generally available of whether buildings were           Standardise the way the
                   industrial/residential/schools/hospitals etc.                population is attributed

                   Datasets often cross referenced with postal delivery
                   point datasets to assist with development of dataset of
                   population distribution.

                   Some issues with mixed use buildings, as common in
                   cities, which may mix commercial shops/offices (often at
                   ground floor level) with residential units (often above) –
                   but this is just an example of the many uncertainties in
                   developing a population distribution dataset
Sound absorption
buildings
                   Data generally not available – input of specific values      No
                   not consistent with strategic noise mapping – may be
                   relevant in some cases for specific action planning cases    Default value(s) should be
                   – use of default values acceptable                           specified in guidance

Number of floors

                   Datasets available in some cases, and can be very useful     No
                   for the assignment of population to buildings
                                                                                  Not relevant in aircraft for
                      The number of floors is more important to the estimation    strategic mapping
                      of exposed populations than the total height of the
                      building to the determination of noise levels.

                       (Not sure this always true – e.g. dwellings over
                      commercial, where commercial rooms may be taller than
                      norma) A. Bloomfiled

Total height of the
building
                      Datasets of building height was often not available.        No

                      Building heights could be supplied through commercial       Documentation of approach
                      products, or specifically commissioned LiDAR/laser          to be mandatory
                      scanning, or 3D photogrammetric work, and is often to a
                      resolution of a few centimetres – this makes for            Not relevant in aircraft for
                      attractive 3D views, but is a level of resolution           strategic mapping
                      unnecessary for strategic noise mapping.

                      Acceptable resolution using current methods for strategic
                      mapping is to use building height classes typically in 4m
                      intervals. This could be estimated by visual site survey,
                      assumptions based upon building footprint/usage data or
                      counting the number of floors.

                      For strategic assessment 8m default from GPG isn’t
                      necessarily “wrong”, but its use should not be
                      mandatory, as better available data should be used if
                      available.

Height per floor

                      Seldom available for specific buildings or cities, when     No
                      available often as a city average, or national average or
                      “typical” value                                             Not relevant in aircraft for
                                                                                  strategic mapping
Altitude of base
contour
                   Not generally available as source dataset. May be             No
                   available when LiDAR/laser scan survey, or 3D photo
                   interpretation, has been undertaken. Therefore could be       Not relevant in aircraft for
                   costly to produce, and not required in most noise             strategic mapping
                   mapping software packages.

Roof shapes

                   Flat roof polygon is acceptable for strategic noise       Flat top roof mandatory
                   mapping. Height assigned could be eves, apex or
                   somewhere between the two, not hugely important which Not relevant in aircraft for
                   (see discussion on building height elsewhere), but should strategic mapping
                   be consistent and documented within model.

                   Realistic roof shapes instead of a single flat roof polygon
                   is relevant only for local high quality fine tuning of
                   noise reduction measures.

                   (But this can be very complex – sometimes better to
                   simplify as compromise – so likely to always need
                   judgment on each case. Should give guidance on how to
                   make best choice – generally better to underestimate true
                   height (gives worst case/precautionary values of noise
                   behind building)). A. Bloomfield

Assignment of
noise levels to
dwellings          There was strong support for the view that if the purpose     Use of façade receptors to be
                   of the strategic noise mapping is to undertake a              mandatory
                   population exposure assessment, then the only
                   appropriate location for receptors is actual on building      guidance issued on location
                   facades, and that a receptor grid is not relevant and         of receptors
                   should not be used.
                                                                                 Not that relevant in aircraft
                   When façade receptor locations are used, interpolation        for strategic mapping
                   from grids is avoided, and assignment of noise to
                   buildings is avoided as you actually have a dataset of
                   façade noise levels, each attributed with a building ID,
                   without having to run some for of estimating or
                  assignment process.

                  Most exposed façade for reporting. However, noise maps
                  should provide noise levels all around the dwellings
                  regardless of the type of rooms and their orientation, to
                  allow specific assessment and solution (W. Babisch)

Population data

                  Large variation in resolution of available population data   Documentation of approach
                  between assessment areas across MS.                          to be mandatory

                  Some MS have actual numbers of people per dwelling           It should be the same for all
                  and data on location and numbers of dwellings within         sources
                  buildings (this is probably the best possible case). Other
                  MS may capture data on numbers of people per dwelling
                  through Census, but do not make it available at such a
                  resolution due to security and/or privacy issues, rather
                  they publish as Census output area or post code level of
                  resolution (possibly average of around 100 dwellings per
                  no. of people). In other MS population data may only be
                  available as estimates at district, borough or city level,
                  and there may be no available information on the
                  number of dwelling units within buildings.

                  These differences lead to bias in the number of people
                  assigned to dwellings. This bias may be consistent across
                  each single assessment area, however there will be large
                  variance between assessment areas, as shown form the
                  results of the research in the first Defra accuracy study
                  NANR 93.

                  Population, residents, building, storeys, dwellings,



Population
assignment
                  See also discussion on grid spacing below.                   No

                  Due to issues around interpolation from grids to building    Documentation of approach
                  facades there was strong support for the view that noise     to be mandatory
                  levels should be assessed at building facades in support
                  of population exposure assessments, and they should not      It should be the same for all
                  be assessed in grids.                                        sources

                  In the face of such gross variations in basic source data
                  (discussed above in Population data), ideas such as “all
                  population of building on most exposed façade” (which
                  assumes all dwellings have multiple aspects) versus
                  “distribution of population around all facades” (which
                  assumes there are no single aspect dwellings within the
                  building), could be considered to be macros scale
                  manipulation of the statistics and will again lead to the
                  introduction of an additional form of bias unless the
                  underlying assumptions are true (which is unlikely to be
                  known)

                  Ultimately it will be another form of variance, and as the
                  resolution of the source datasets for population numbers
                  cannot be made a mandatory specification, it will not be
                  possible to remove the bias.

                  For strategic maps, best to assign all to noisiest facade
                  (precautionary principle), but for local action plans will
                  need to consider true location of habitable rooms (e.g.
                  well designed buildings may place only non-habitable
                  rooms on noisiest facades) A. Bloomfield

Barriers height

                  Barriers should be discussed as “screens”, as barriers       Not relevant for aircraft in
                  distracted discussion towards “specifically constructed      flight. It is for ground
                  noise barriers” which was not appropriate.                   operations

                  Discussed attempted to discuss wider aspects of
                  “screens” which may be noise barriers, may be walls,
                  may be edges of cuttings etc

                  As with digital terrain discussed above, important to
                  consider that screens may be modelled in software as
                  “barrier/screen” objects, retained cuttings, escarpment
                      edges or top of slope objects. They may be 2D + height
                      objects or full 3D objects.

                      Z data is generally more important, and more expensive
                      to obtain. Barrier data may need to be collected from
                      detailed field survey, estimated via simple field survey,
                      or via 3D photo interpretation.

Barrier position

                      Often not available in reliable forms, even from             Not relevant for aircraft in
                      highways authorities who may have funded construction        flight. It is for ground
                      of noise barriers.                                           operations

                      May be possible to ascertain from aerial photography, or
                      may require field surveys to identify and locate.

Sound absorption
barriers
                      Field survey may be able to assign barrier materials into    Defaults based upon classes
                      various typical classes (wood, concrete, transparent, etc)   Not relevant for aircraft in
                      and default values per class assigned                        flight. It is for ground
                                                                                   operations
Tunnels

                      Not discussed                                                Guidance issued based upon
                      depends upon method of assessment and ability of noise       capabilities of method of
                      mapping software to model a tunnel opening                   assessment

                      How to model tunnel mouths? A. Bloomfield

Meteorological data

                      See above                                                    See above

                      What to use? Local measurements, global assessment,
                      modelling based on 3-D measurements

                      At least in some countries, large time series of
                      meteorological data are available. They can be used to
                               compute probabilities of propagation classes (downward,
                               upward, homogeneous) for most infrastructures. The
                               case of urban areas is more difficult to address.

Grid spacing

               E.g.            This discussion actually expanded to discuss the whole        Guidance issued               ECAC doc29 3rd       no
               <0.5dB          issue of what the appropriate location of assessment                                        ed. gives guidance
               difference      points actually is.                                           Documentation of process      (also irregular
               for                                                                           mandatory                     grids)
               interpolation   There was strong support for the view that if the purpose
               from            of the strategic noise mapping is to undertake a              For aircraft noise contours
               100x100 to      population exposure assessment, then the only                 ≈100m is ok. Higher
               10x10           appropriate location for receptors is actual on building      resolutions can be derived
                               facades, and that a receptor grid is not relevant and         from that.
                               should not be used. Location of façade receptors would
                               then require guidance – horizontal/vertical spacing,          Industry 10m probably ok
                               minimum façade length, distance from façade etc

                               If this approach is accepted, the only purpose of a grid
                               calculation is to provide plan view maps of noise across
                               wide areas using coloured gradients or squares.
                               (isophone noise level contours were disliked by a large
                               proportion of the delegates as they produce an indicated
                               level of precision which is not supported by the
                               underlying datasets of grid noise levels – they appear to
                               show 0.1dB resolution across the noise contour line,
                               when they may actually have uncertainties of +-5dB) –
                               gradients and squares as less precise presentations, and
                               more appropriate given the underlying noise assessment
                               data – see WG-AEN Position Paper on presentation to
                               the public for similar guidance

                               For production of pictures from receptor grids, the
                               appropriate grid spacing is determined by the smallest
                               scale of display the results will be provided at. E.g. most
                               public websites displaying strategic noise mapping
                               results do not provide results below approximately
                               1:5000 scale, in which case a 30m or 20m grid may be
                               more than enough resolution to provide an acceptable
                               results set for the public maps.
              A 10m grid may only be necessary if results are to be
              displayed at 1:1000 scale, or are to be used as the basis
              of population impact assessment.

              10m is good compromise (accuracy vs. computation
              time) at present, but allow for software that can
              automatically use smaller grid spacing near buildings
              etc. A. Bloomfield

              Important issue. Exposure on the shielded side is often
              overestimated with respect to effects (e. g. sleep
              disturbance), because for indoor noise the sound level
              right in front of the window (1m) is relevant, not the grid
              level, e. g. 10 meters behind the building. W. Babisch

Uncertainty

              The uncertainty introduced by the use of default values,      Guidance should be issued
              or low accuracy/resolution datasets (compared to best
              available data) cannot be assessed without knowledge of       Uncertainty should be
              the method of assessment. The two Defra studies can           assessed based upon guidance
              provide some indication on the “likely” order of merit of
              datasets, and the “possible” levels of uncertainties;
              however the results are specific to the calculation
              methods investigated. Any proposed Common Method
              would require a similar investigation in order to provide
              GPG type guidance which is anything other than a “best
              estimate”.
                                                       ROAD
Low flow roads

                 Rather than discuss “low flow roads” we           Mandatory
                 discussed “roads without known traffic flows”     treatment
                 as this is actually the case which is faced.
                                                                   Guidance should
                 It was agreed that:                               be issued
                 - “we will never have genuine traffic flows for
                 all the roads within an agglomeration map”      Uncertainty should
                 - “within an agglomeration all roads should be be assessed based
                 included within the assessment as               upon guidance
                 recommended by GPGv2” – omission of roads
                 considered dangerous, however highly detailed
                 and accurate was considered unnecessary and
                 highly challenging
                 - therefore we will always face a situation
                 where roads which must be included within the
                 assessment have unknown traffic flows

                 The current approaches to filling this gap in
                 data ranges significantly, from total omission,
                 to inserting a single default value into all
                 unknown roads. These choices may be on a
                 project by project basis, and vary within and
                 between MS. This variation totally
                 compromises reliable comparisons. Look at
                 pictures of maps from German cities compared
                 within English cities (not London) for the
                 contrast.

                 GPGv2 toolkit provides guidance on the
                 possible approaches to developing datasets,
                 and provide an approach to assigning default
                 flows. However there were many different
                 possible approaches to assigning various
                 default flows for unknown flows.
                      Proposed that GPGv2 toolkit approach should
                      be investigated further, and a single approach
                      set out in future guidance for use in strategic
                      noise mapping.

                      Need to be careful when using default or
                      estimated values as many small residential
                      roads have small flows – overestimation of
                      flows will greatly distort maps, due to large
                      number of such roads. (Also – can method
                      handle small flows accurately?). A.
                      Bloomfield

                      Another question is whether intermittent light
                      traffic should be included at all, because
                      perceived as individual events, not continuous
                      source – so Leq based indicator not
                      appropriate? A. Bloomfiled

                      Road surface, speed and acceleration
                      extremely important. Small numbers of high
                      Lmax may be more relevant for effects (e. g.
                      sleep disturbance) than constant background
                      hum with same (low) Leq. W. Babisch

Infrastructure
position
                      Z more important than X, Y position. GPG
                      guidance not questioned, but any specific
                      values should be related to the methodology

Number of road line
sources
                      Depends upon what is available. In some MS        Guidance should
                      for some roads there are lines per lane, others   be issued
                      have lines per carriageway, others have lines
                      per road.                                         Uncertainty should
                                                                        be assessed based
                      No specific rules, and it depends upon what is    upon guidance
                      available, how the flow data is managed (by
                        lane, carriageway or road) and how the method
                        of assessment may treat the differences
                        between the carriageways – eg uphill/downhill
Position of road line
sources (knowledge
on number of lanes,     Most assessment methods use road (or              Guidance should
width)                  carriageway or lane) centrelines and locate the   be issued
                        emission points along this line. This is
                        acceptable as centreline data is typically        Uncertainty should
                        available.                                        be assessed based
                                                                          upon guidance
                        Some legacy methods do not have the
                        emission at the centreline, but they may be
                        configured in software to use a centreline.

                        Where road (or lane or carriageway) width is
                        required as an attribute, it is not generally
                        known, rather it may be estimated using GIS
                        techniques if the road edges are known, or
                        default values assigned per road class

Road gradient

                        Road gradient is used in a number of              Guidance should
                        assessment methods, however it is seldom          be issued
                        input as an attribute from input datasets
                                                                          Uncertainty should
                        Commonly it is assessed by the noise mapping      be assessed based
                        software at run time, or as a pre-processing      upon guidance
                        stage, based upon the draping of the road
                        centreline onto the underlying ground model.

                        This can lead to issues, and should undergo
                        review and sign off prior to final calculations
                        in order to avoid localised issues with
                        automatically draped centrelines

Ground elevation
close to road
                        As discussed above in General Parameters, it      Guidance should
                  is seen as the most important parts of the        be issued
                  ground model, the corridor of information
                  either side of the road.                          Uncertainty should
                                                                    be assessed based
                  Cuttings, embankments, barriers and buildings     upon guidance
                  within short distance of the sources should be
                  collected in the best available resolution

Speed

                  Genuine speed data was almost never available Guidance should
                  during the noise mapping process              be issued

                  Most projects seemed to use default speeds        Uncertainty should
                  based upon the speed limit for the section of     be assessed based
                  road being modelled.                              upon guidance

                  There were some other approaches such as
                  modelled speeds, GPS capture, speed surveys,
                  however they were not widely used

Acceleration

                  Acceleration / deceleration zones may be          Guidance should
                  modelled in some methods, however it was          be issued
                  generally considered useful only for localised
                  action plan detailed assessments, whilst
                  strategic noise maps should generally ignore
                  such aspects – as with junctions, roundabout
                  etc

Flow (number of
vehicles)
                  Flow categories were discussed, rather than       Guidance should
                  number of vehicles.                               be issued

                  Many current methods have two flow                Uncertainty should
                  categories, light/heavy. It was considered that   be assessed based
                  3 or 4 categories of vehicles is probably         upon guidance
                  appropriate for strategic noise mapping, but
                      possibly with the ability for more categories if
                      required under local action plans.

                      Traffic flow data may come from traffic
                      models, traffic counts or capacity forecasting.
                      These generally do not provide real speed
                      information.


Heavy/light
classes
                      See above discussion on flow and categories

Scooters/motorbikes

                      Of particular interest to some MS. See             Must be available
                      discussion on flow and categories above, but       within source
                      generally suggested that these remain a            model and vehicle
                      specific vehicle flow category for MS who          categories
                      require their assessment.

Road surface

                      GPGv2 provided a number of                         Guidance should
                      recommendations on corrections for various         be issued
                      road surface types.
                                                                         Uncertainty should
                      In strategic mapping the global changes may        be assessed based
                      only require a small number of surface             upon guidance
                      categories, however action plans may require 6
                      or 7 classes of road surface, and may be
                      important to demonstrate improvements
                      possible from re-surfacing

                      important (see low flow roads) W. Babisch

Car tyres

                      Global corrections for population of national      Guidance should
                      tyre constitution may be modelled within           be issued
                     Harmonoise source term
                                                                        Uncertainty should
                     Most considered data currently unavailable,        be assessed based
                     however it was admitted that nobody had            upon guidance
                     looked for it at present.

                     Relevant to provide evidence to support noise
                     in tyre directive, and relevant to assess
                     potential future changes to tyre directive


Engine noise

                     Harmonoise source model may be used to             Guidance should
                     assess changes, however it would require use       be issued
                     of defaults across strategic mapping, but may
                     be useful for specific action plan approaches      Uncertainty should
                     such as low emission zones – would also be         be assessed based
                     relevant in strategic maps if such areas already   upon guidance
                     existed

Embankment height

                     See ground elevation close to road above, and
                     discussion on digital ground model in General
                     Parameters above

Crossings /
junctions
Speed fluctuations   Largely considered to be of potential relevance    Not for strategic
                     to local action plans, however considered          noise mapping
                     excessive detail for strategic noise maps.
                                                                        Required for action
                                                                        plans

                                                                        Guidance should
                                                                        be issued
Parking lots

                     May be relevant to local action plans, not         Not for strategic
                     considered necessary for strategic noise maps.     noise mapping
                     Method should support there use, but they
                     should not be mandatory for assessment             Required for action
                                                                        plans

                                                                        Guidance should
                                                                        be issued

Low emission zones

                     The Harmonoise road vehicle source term            Guidance should
                     supports the modelling of hybrid/electric          be issued
                     vehicles as the tyre/road, engine and
                     aerodynamic sources are separated from each
                     other. However there was no experience of
                     modelling low emission zones or congestion
                     charge zones.

                     Could be relevant to both local action plans (as
                     a what if scenario assessment) but also
                     strategic noise maps for zones which are in
                     place.

General points

                     - all issues associated with data quality
                     requirements should be specifically related to
                     the method of assessment
                     - data specifications are driven by the method
                     of assessment, it must be known before specs
                     and quality targets may be developed
                                                         RAILWAY
Infrastructure
position
                      Z more important than X, Y position. GPG             Guidance should
                      guidance not questioned, but any specific            be issued
                      values should be related to the methodology
                                                                           Uncertainty should
                      See discussions below on source position             be assessed based
                                                                           upon guidance

Number of railway
line sources
                      Depends upon what is available. In some MS           Guidance should
                      for some railways there are lines per railhead,      be issued
                      others have lines per rail line, others have lines
                      per corridor.                                        Uncertainty should
                                                                           be assessed based
                      No specific rules, and it depends upon what is       upon guidance
                      available, how the flow data is managed (by
                      line, corridor or route) and how the method of
                      assessment may treat the differences between
                      the lines

Position of railway
line sources
                      Most assessment methods use rail centrelines         Guidance should
                      and locate the emission points along this line.      be issued
                      This is acceptable as centreline data is
                      typically available.                                 Uncertainty should
                                                                           be assessed based
                      Z information can be more of an issue than           upon guidance
                      with roads, particularly due to multiple
                      emission heights from rail vehicles. The
                      interaction between high level sources and
                      cuttings/barriers can be more critical than with
                      roads
Ground elevation
close to railway
                   As discussed above in General Parameters, it     Guidance should
                   is seen as the most important parts of the       be issued
                   ground model, the corridor of information
                   either side of the railway.                      Uncertainty should
                                                                    be assessed based
                   Cuttings, embankments, barriers and buildings    upon guidance
                   within short distance of the sources should be
                   collected in the best available resolution

                   See also discussion on position of line source
                   above

Speed

                   Genuine speed data was almost never available Guidance should
                   during the noise mapping process              be issued

                   Most projects seemed to use default speeds       Uncertainty should
                   based upon the line speed limit and the rail     be assessed based
                   vehicle maximum speed for the section of rail    upon guidance
                   being modelled.

                   There were some other approaches such as
                   modelled speeds, GPS capture, speed surveys,
                   talking with train drivers etc however they
                   were not widely used

Acceleration

                   Acceleration / deceleration zones may be         Guidance should
                   modelled in some methods, however it was         be issued
                   generally considered useful only for localised
                   action plan detailed assessments, whilst there
                   was some disagreement regarding their role in
                   strategic noise maps

                   Some argued for inclusion, others for
                   exclusion on the basis of complexity, possible
                   compromise is the Dutch assumption of
                       40km/h modelling through stations for all
                       trains

Flow (number of
trains)
                       Flow categories were discussed, rather than        Guidance should
                       number of vehicles.                                be issued

                       Many current methods have two flow                 Uncertainty should
                       categories, light/heavy. It was considered that    be assessed based
                       3 or 4 categories of vehicles is probably          upon guidance
                       appropriate for strategic noise mapping, but
                       possibly with the ability for more categories if
                       required under local action plans.

                       Traffic flow data may come from traffic
                       models, traffic counts or capacity forecasting.
                       These generally do not provide real speed
                       information.


Train classes (IC,
High speed, local,..
freight type 1,        EC recommended Interim Method, and Dutch           Vehicle classes as
freight type 2)        RMR, use train classes                             preferred approach

                       Most other methods use vehicle classes. Group
                       was strongly in favour of a vehicle based
                       approach to modelling, and avoiding a train
                       based approach to modelling.

                       The Dutch do not need to match trains to
                       categories as the ASWIN database is supplied
                       fully populated and the Dutch use it “as is” –
                       so there is no experience of the problem faced
                       by the remainder of EC

                       Matching non-Dutch trains to Dutch train
                       categories is time consuming and trick
                       business which can introduce bias, as shown in
                        Defra research NANR 208

                        Only aware of Austrian and Spanish efforts to
                        create new train sources for the Interim
                        method. Most did not bother due to complexity
                        of method set out in Wolfel Guidance.

                        Some evidence of localised ad-hoc validation
                        measurements on some trains to help select
                        Dutch train, but this was not considered robust.

Vehicle classes
(alternative to the
previous, if detailed   Methods using rail vehicles as the source           Preferred approach
information needed      objects were much preferred, as any train
on the vehicle          could be composed from underlying vehicle           Guidance should
types)                  objects                                             be issued

                        Key issue is that the means by which new            Uncertainty should
                        vehicles may be added to the database should        be assessed based
                        be practical and straightforward for typical        upon guidance
                        field measurement approach desired by MS.

                        It was suggested that Imagine rail vehicle
                        database provides a good starting point, and
                        that the measurement protocol was designed to
                        be practical in order to help expand the
                        contents of the database.

Railway roughness

                        It was considered that the modelling of             Guidance should
                        railhead roughness is very important for local      be issued
                        action plan development, and may have
                        benefits at national level.                         Uncertainty should
                                                                            be assessed based
                        It was suggested that data on railhead              upon guidance
                        roughness was often available; however it was
                        not readily released due to the link with safety.

                        Default values could be assigned, and localised
                       data supplemented for action plans if required

                       Some evidence reported that in Germany some
                       lines are better maintained, and have lower
                       railhead roughness levels, than others. These
                       maintained tracks could be alongside non-
                       maintained tracks, but used for specific
                       services such as high speed trains

Rail type, Pad type,
Sleeper type,
Ballast                Not discussed in any detail during the             Guidance should
                       workshop                                           be issued

                       Information is required on each as it is relevant Uncertainty should
                       to the emission model. It may or may not be       be assessed based
                       available, thus it should be a part of the        upon guidance
                       common method, however guidance will be
                       required on the use of defaults for situations
                       where it is unavailable. Appropriate default
                       values can be developed as a result of
                       uncertainty testing.

Wheel roughness
(see also vehicle
classes)               Wheel roughness, particularly on freight trains    Guidance should
                       at higher speeds, can be a dominant source,        be issued
                       and its omission can lead to large uncertainties
                       in results. However genuine data can be            Uncertainty should
                       difficult to obtain, and often handled via         be assessed based
                       defaults based upon brake block composition        upon guidance

                       At low speeds the railhead roughness tends to
                       dominate

                       Can be relevant factor in local or national
                       action plans, such as brake stock replacement
                       or routing of freight trains, or possibly action
                       plan items such as night time bans
Engine noise

                       Part of rail vehicle source model, see
                       discussions elsewhere

Breaking noise

                       The issue of acceleration/deceleration and       Guidance should
                       stations are related to breaking noise, and      be issued
                       discussed elsewhere in this list

Embankment height

                       See ground elevation close to road above, and
                       discussion on digital ground model in General
                       Parameters above

Crossings / switches

                       These are known to have localised impact, and    Guidance should
                       may produce significant changes in noise level   be issued
                       within close proximity, however developing a
                       dataset of locations can be difficult, as can    Uncertainty should
                       editing the source line to include the on/off    be assessed based
                       nature of the switch correction attribute.       upon guidance

                       Overall they are probably more relevant to
                       local action planning measures than strategic
                       noise mapping, however any common method
                       must include the ability to model them.

Railway stations

                       There was some discussion of stations, and       Guidance should
                       arguments for and against there inclusion in     be issued
                       strategic noise mapping.
                       Some argued for inclusion, others for            Uncertainty should
                       exclusion on the basis of complexity, possible   be assessed based
                       compromise is the Dutch assumption of            upon guidance
                       40km/h modelling through stations for all
                        trains.



Squeal noise

                        It was suggested that common culprits may be       Guidance should
                        identifiable based upon train type and track       be issued
                        curve radius, however it is not necessarily
                        straightforward or of high significance within     Uncertainty should
                        a strategic assessment, although it can be of      be assessed based
                        considerable important to local population.        upon guidance

                        This lead onto the discussion on light rail

Light rail, trams and
underground trains
on surface tracks       Light rail and trams are becoming increasingly     Further research is
                        relevant as they are seen as a solution to urban   required to develop
                        mobility in a number of European cities.           better source
                                                                           models for light
                        The current systems can be grouped into two        rail / trams etc and
                        categories, old legacy systems and new             develop a database
                        modern systems.                                    of emission
                                                                           parameters for
                        In general the source emission models for          vehicles in service
                        these various groups of light rail vehicles has
                        not been investigated in any detail, and the
                        models are not fully developed.

                        It is considered important that light rail/tram
                        systems are included within strategic noise
                        maps; however the method of assessment is
                        not clear. In general it was agreed by those
                        with experience that every light rail vehicle is
                        type is different, and therefore to date any
                        modelling has been based upon measurements.

                        Due to the lack of method, there is therefore a
                        lack of source data, and no agreed means of
                        addressing the issue.
                   It may be possible to use existing source
                   models for light rail, however the relevant
                   parameter values have not been investigated.

                   It would appear that light rail and tram systems
                   need further research in order to develop
                   suitable source models and provide guidance
                   on a suitable approach to their inclusion within
                   strategic noise mapping.

General comments

                   One comment was made that railway
                   modelling methods are becoming so complex
                   that only railway noise experts and rail
                   companies can actually undertake the
                   modelling. This lead to a discussion on the
                   whole issue of competent authority, asset
                   owner and action planning. As is often the case
                   with airports, there was some disquiet
                   regarding the asset owners being the noise
                   mapping body and the action planning
                   authority.

                   Data ownership, openness with the public and
                   ability for local authorities to undertake
                   actions at airports, railways and national
                   highways was raised as a barrier to delivering
                   action plan objectives, but this is really a wider
                   policy discussion.
                      INDUSTRIAL
Source geometry
(point, line, area,
etc,..)
Source position


Sound power
database

Directivity



Ground elevation
close to railway

Temperature



Humidity


Ground absorption
                                                                  AIRCRAFT


Radar tracks

                    3- 5 dB       This should possibly be separated in           Not because of        Consistency between        No
                                  - Ground track                                 property issues and   INSPIRE and END: if END
                                  - Flight profiles                              unavailability        require, then INSPIRE as
                                                                                  But you should       well.
                                  Depends on the information of the routes and   possibly have it.
                                  the use of the runway


                                  Dependent on distance from airport
Track dispersions
lateral

Track dispersion
vertical
                    <1dB          Important close to airport                     If radar tracks     For performance ECAC         No
                    TakeOff       Can be taken from radar tracks or from         available, see      Doc29 3rd ed.
                    <3dB          performance calculations                       above
                    Approach      Takeoff is performance based                   Otherwise up to the
                     (if only     Landing air navigation based                   modeller
                    position is
                    considered)

Sound power
database
                                  Relevant for spectral based methods            Mandatory to have
                                                                                 a single database
                                                                                 for all MS
Directivity

                                  Relevant for spectral based methods            Mandatory to have
                                                                                a single database
                                                                                for all MS

NPD data

                   Cert data   Relevant for integrated methods                  Mandatory to have   Procedure to record the MS
                   0.3dB       Public data accuracy unknown. Advise from        a single database   dependent corrections
                               manufacturers required                           for all MS
                                Corrections to certain aircrafts might be
                               necessary (according to agreed procedure), but
                               should be same to all MS. Other corrections
                               might be MS dependent (e.g. atm conditions)

Performance
database
                   Cert data   Relevant for integrated methods                  Mandatory to have   Procedure to record the MS
                   0.3dB??     Public data accuracy unknown. Advise from        a single database   dependent corrections
                               manufacturers required                           for all MS
                                Corrections to certain aircrafts might be
                               necessary (according to agreed procedure), but
                               should be same to all MS. Other corrections
                               might be MS dependent (e.g. atm conditions).
                               Fixed point profiles need corrections for non-
                               ref conditions.

Ground elevation

                               See above
Meteo on
performance
                               Taken into account in modelling

Meteo on
propagation
                               Wind difficult to quantify for aircraft
                               Atm absorption for non-reflective conditions
Aircraft type fleet
(grouping +
substitutes)                       If data for individual aircraft types are        Mandatory list for
                                   available it should be used. If not, or if       substitutes,
                                   computation time does not allow, grouping        Guidelines for
                                   should be possible.                              grouping required.
                                   For unknown aircraft types substitutes should
                                   be defined.

Weight



Flight conditions

                      Can give     If the model is based on fixed point profiles,                        Need for standardisation
                      bias of 1-   no issue.                                                             and guidelines
                      2dB          If you can choose, it is. Which profile best
                                   suits an airport is a local issue.

Reflections on
ground

Reflection on
buildings

Shielding

                                   Most exposed façade. Effect of shielding less
                                   important compared to other sources (in the
                                   distance). Close to the airport spectral
                                   differences (windwards/leewards) W. Babisch


Spectral
information
Special approach
instructions

Special departure
instructions

Ground operations



Taxiing
                    Norway took into account
                    Amsterdam only taking off taken into account

Definition of
movements to be
mapped              E.g. military, helicopters, GA ops on a civil
                    airport

				
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