Urban roads

Munch, D. 1993. Concentration prohles of arsenic, cadmium, chromium, copper, lead, mercury, nickel, zinc, vanadium and polynuclear aromatic hydrocarbons (PAH) in forest soil beside an urban road. Sci. Total Environ. 138 47-55. 

Urban roads Severe congestion in some cities, no general problem C v Steadily increasing but not perceived a major problem D v... 

Tervahattu H, Kupiainen KJ, Raisanen M, Makela T, Hillamo R (2006) Generation of urban road dust from anti-skid and asphalt concrete aggregates. J Hazard Mater 132 39-46... 

Kupiainen K, Tervahattu H, Raisanen M (2003) Experimental studies about the impact of traction sand on urban road dust composition. Sci Total Environ 308 175-184... 

Patra A, Colvile R, Arnold S, Bowen E, Shallcross D, Martin D, Price C, Robins A (2008) On street observations of particulate matter movement and dispersion due to traffic on an urban road. Atmos Environ 42 3911-3926... 

While most of the noble metal stays on the catalyst, small amounts do end upon the road, causing diverse environmental effects [115-117]. The concentration of Pt metals in urban road dust (especially on roundabouts) can be 100-fold higher than the normal background concentration. There is even a company in the UK that sweeps up this dust, with the aim of recovering the Pt group metals ... 

Motelica-Heino, M., Rauch, S., Morrison, G.M., Donard, O.E.X. Determination of palladium, platinum and rhodium concentrations in urban road sediments by laser ablation-ICP-MS. Anal. Chim. Acta 436, 233-244 (2001)... 

The most common road de-icing practice is to apply pure sodium chloride to main urban roads and highways. Calcium chloride is also used but not as frequently, since it is more expensive and is known to make road surfaces more shppery when wet (Richter et al., 1993). Hence, the most important geochemical signal of road de-icing is typically an Na-Cl solution with an Na/Cl ratio close to unity (Table 1 Howard and Beck, 1993). The use of calcium chloride results in contamination with Ca-chloride solutions with an Na/Cl 1. 

Earago me, Kavanagh P, Blanks R, Kelly J, Kazantzis G, Thornton I, Simpson PR, Cook JM, Parry S and Hall GM (1996) Platinum metal concentrations in urban road dust and soil in the United Kingdom Fresenius J Anal Chem 354 660-663. 

Human panel studies, since they have a relatively small number of subjects who can be closely monitored, offer the opportunity to obtain excellent exposure information. Personal pollution monitors can be used a mobile monitor can follow residents of a retirement community as they go about group activities a monitor within 100 m of a major urban road can assess pollution for those living in similar proximity to the same road monitors can be placed inside and just outside a home. 

PMSs may be developed for either a rural or an urban network the principles for developing such systems or programs are the same. However, because of the differences in data reference system, functionality and priority policies, a PMS for a rural and an urban network should be developed separately. A differentiation may also exist among PMSs for motorway, national or provincial urban roads. In any case, a PMS is developed for the network level or project level. 

Urban population Urban roads will have more accidents and fewer fatalities or severity per kilometre travelled than rural roads, because of the density of vehicles and the lower speeds of travel. Hakkert and Braimaister (2002) have shown in one macro-study that countries with a high level of urbanisation will have higher population densities and they may experience lower levels of fatalities and serious injuries. Page (2001) has found that the population who hve in urban areas have fewer road accident fatalities than other places. Bester (2001) also reported similar results that countries with higher road densities will have fewer fatality rates. Shorter distances to medical services can explain this. 

Third, the indicators chosen should be clear and with a precise definition. For example, an indicator of safer vehicles or urban roads standards without a clear and precise definition of what we mean by the words safe or standards could easily lead to as unclear collection of data. This will likely lead to a misunderstanding of what results are being achieved. 

The table below shows the proportion of accidents at different locations and their relative accident rates. Not surprisingly, the largest proportion of accidents occurs on urban roads given the size of the road network and the mix of road users. Motorways have the lowest accident rate. 

TRL Report 510 Accidents at junctions on one-way urban roads, 2001 For all junction types, there was no evidence that the presence of pedestrian guardrail was associated with fewer pedestrian accidents. 

The laying of a new water pipe involves excavating along and across an urban road. The width of the carriageway will be restricted to a single lane during the work and traffic flow in both directions is to be maintained. 

Whittles, M. J. 2003. Urban Road Pricing Public and Political Acceptability. Aldershot, U.K. Ashgate. Based on a PhD thesis, this discusses data on public attitudes to various road-pricing options and how they might be addressed. 

Barbosa, H.M. 1995. Impacts of traffic calming measures on speeds on urban roads. PhD thesis. Leeds Institute for Transport Studies, University of Leeds. 

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