Methoden voor de berekening van de emissies door mobiele ... - CBS

shown in Table 1.19A. The emission factors originate from the fact sheet "emissions of brake linings"
drawn up by the Centre for Water Management of the Ministry of Public Works and Water
Management. [ref 107: CWM]. It is assumed that the material emitted from brake linings is comprised for
49% of particulate matter (PM10) and for 20% of larger fragments. The remainder of the material (31%)
remains "on the vehicle".
The share of PM2,5 in PM10 is estimated 15% (see table 1.42).
Wear of road surface caused by road vehicles
The emissions of road particulate matter are calculated in the same way as the emissions of tyre and
brake lining particulate matter. To link up with the earlier estimates of total road wear [WSV, 1994] it is
assumed that the emission of road particulate matter is 1.6 times as large as that of tyre particulate
matter emission. This factor is assumed to be independent of the statistical year. For the emission
factors is referred to Table 1.15. In the same way as with tyre wear, it is assumed that 5% of the road
particulate matter emission comprises particulate matter (PM10) and that the remainder therefore
comprises larger fragments.
The share of PM2,5 in PM10 is estimated 15% (see table 1.42)
Figure 1.5 Calculating emissions from road traffic, emissions of particulate matter (PM10)
caused by wear of tyres, brake linings and road surfaces
EMISSION FACTORS
total wear debris mg/vehicle km
per vehicle category
EMISSIONS total wear debris
1000 kg
per
- vehicle category
- fuel type
- road type
EMISSIONS particulate matter
per
- vehicle category
- fuel type
- road type
1000 kg
VEHICLE
KILOMETRES
per
- vehicle category
- fuel type
- road type
PROFILES
particulate matter/
larger debris
Wear of tyres, brakes and road surfaces; heavy metals and PAHs
Heavy metals in tyre particulate matter emission
The emissions of heavy metals caused by tyre wear are calculated by applying a profile of the
composition of the total tyre material. This composition is shown in Table 1.29B. The heavy metals
trapped in particulate matter are emitted to the air because it is assumed that 100% of particulate
matter remains airborne. Heavy metals trapped in coarse particles fall back to the soil or the surface
water. Within the urban area, it is assumed that 100% of coarse particles end up in water. Outside the
urban area, a figure of 10% is used, and therefore 90% end up in the soil [ref 118: RWS Centre for Water
Management].
Heavy metals in brake particulate matter emission
The emissions of heavy metals caused by the wear of brake linings are calculated by applying a profile
of the composition of brake lining material. The composition profile is shown in Table 1.29B. This table
is derived from Table 6 of the fact sheet "emissions from brake linings" [ref 107: RWS Centre for Water
Management]. For the allocation of the emissions of heavy metals to soil and water as a result of brake
lining wear, the same percentages are used as with tyre wear emissions.
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