Denmark's National Inventory Report 2005 - Submitted under the ...

2) Quantification of use amounts from Eq.1
3) Quantification of emission factors for each chemical
In principle all chemicals that can be classified as NMVOC must be included in the analysis, which
implies that it is essential to have an explicit definition of NMVOC. The definition of NMVOC is,
however, not consistent; In the EMEP-guidelines for calculation and reporting of emissions,
NMVOC is defined as ”all hydrocarbons and hydrocarbons where hydrogen atoms are partly or
fully replaced by other atoms, e.g. S, N, O, halogens, which are volatile under ambient air conditions,
excluding CO, CO 2 , CH 4 , CFCs and halons”. The amount of chemicals that fulfil these criteria
is large and a list of 650 single chemicals and a few chemical groups described in ”National Atmospheric
Emission Inventory”, cf. Annex 3.F, is used. It is probable that the major part will be
insignificant in a mass balance, but it is not correct to exclude any chemicals before a more detailed
investigation has been made. It is important to be aware that some chemicals are comprised in
products and will not be found as separate chemicals, e.g. di-ethylhexyl –phthalate (DEHP), which
is the predominant softener in PVC. In order to include these chemicals the product use must be
found and the amount of chemicals in the product must be estimated. It is important to distinguish
the amount of chemicals that enters the mass balance as pure chemical and the amount that is associated
to a product, in order not to overestimate the use.
Production, import and export figures are extracted from Statistics Denmark, from which a list of
427 single chemicals, a few groups and products is generated. For each of these a use amount in
tonnes pr. year (from 1995 to 2003) is calculated. It is found that 44 different NMVOCs comprise
over 95 % of the total use, and it is these 44 chemicals that are investigated further.
In the Nordic SPIN database (Substances in Preparations in Nordic Countries) information for industrial
use categories and products specified for individual chemicals, according to the NACE
coding system is available. The use amounts of individual chemicals are distributed to specific
products and activities. The product amounts are then distributed to the CRF sectors 3A – 3D.
Emission factors, cf. Eq. 2, are obtained from regulators or the industry and can be provided on a
site by site basis or as a single total for whole sectors. Emission factors can be related to production
processes and to use. In production processes the emissions of solvents typically are low and in
use it is often the case that the entire fraction of chemical in the product will be emitted to the atmosphere.
Each chemical will therefore be associated with two emission factors, one for production
processes and one for use.
Outputs from the inventory are
• a list where the 44 most predominant NMVOCs are ranked according to emissions to air,
• specification of emissions from industrial sectors and from households,
• contribution from each NMVOC to emissions from industrial sectors and households,
• tidal (annual) trend in NMVOC emissions, expressed as total NMVOC and single chemical, and
specified in industrial sectors and households.
5.2.3 Uncertainties and time-series consistency
Important uncertainty issues related to the new approach are
(i) Identification of chemicals that qualify as NMVOCs. The definition is vague, and no approved
list of agreed NMVOCs is available. Although a tentative list of 650 chemicals from the ”National
Atmospheric Emission Inventory” has been used, it is possible that relevant chemicals are not included.
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