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ENVIRONMENTAL EXPOSURE ASSESSMENT<br />

Explanation of symbols<br />

Elocalair local direct emission rate to air during episode [kg . d -1 ] eq. (5)<br />

Estpair local indirect emission to air from STP during episode [kg . d -1 ] eq. (35)<br />

Cstdair concentration in air at source strength of 1 kg . d -1 [mg . m -3 ] 2.78.10 -4<br />

Temission number of days per year that the emission takes place [d . year -1 ] App. IB<br />

Clocalair local concentration in air during emission episode [mg . m -3 ]<br />

Clocalair,ann annual average concentration in air, 100 m from point source [mg . m -3 ]<br />

Explanation of symbols<br />

74<br />

PEClocal air,ann = Clocal air,ann + PECregional air<br />

(42)<br />

Clocalair,ann annual average local concentration in air [mg . m -3 ] eq. (40)<br />

PECregionalair regional concentration in air [mg . m -3 ] 2.3.8.7<br />

PEClocalair,ann annual average predicted environmental conc. in air [mg . m -3 ]<br />

The calculation of deposition flux is slightly more complex because of the dependence of the<br />

deposition flux on the fraction of the substance that is associated with the aerosols. In calculating<br />

the deposition flux, the emissions from the two sources (direct <strong>and</strong> STP) are summed:<br />

( + Estp ) • ( • + - ) • )<br />

DEPtotal = Elocalair<br />

Fassaer<br />

DEPstd aer (1 Fassaer<br />

DEPstd gas<br />

(43)<br />

Explanation of symbols<br />

air<br />

DEPtotal ann = DEPtotal Temission<br />

•<br />

Elocalair local direct emission rate to air during emission episode [kg . d -1 ] eq. (5)<br />

Estpair local indirect emission to air from STP during episode [kg . d -1 ] eq. (35)<br />

Fassaer fraction of the substance bound to aerosol [-] eq. (19)<br />

DEPstdaer st<strong>and</strong>ard deposition flux of aerosol-bound compounds at a<br />

source strength of 1 kg . d -1 [mg . m -2. d -1 ] 1 . 10 -2<br />

DEPstdgas deposition flux of gaseous compounds as a function<br />

of Henry's Law constant, at a source strength of 1 kg . d -1 [mg . m -2. d -1 ]<br />

10 logHENRY ≤ -2: 5 . 10 -4<br />

365<br />

-2 < 10 logHENRY ≤ 2: 4 . 10 -4<br />

10 logHENRY > 2: 3 . 10 -4<br />

Temission number of days per year that the emission takes place [d . yr -1 ] App. IB<br />

DEPtotal total deposition flux during emission episode [mg . m -2 .d -1 ]<br />

DEPtotalann annual average total deposition flux [mg.m -2 .d -1 ]<br />

(44)

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