Spread calculations and modelling

In many places, there are such high levels of particles in the air that there is a risk that the environmental quality standard for outdoor air will be exceeded. This increases interest in quantifying the particle load from diffuse dusting in stone, gravel and biofuel storage, sand reservoirs, sawmills and bare surfaces in connection with construction.

Through various measurement methods and dispersion calculations, IVL produces generalized relationships between diffuse particle sources and how they contribute to the concentrations in air and the deposition of particles in the environment. By defining emission factors and then estimating the emission, as well as calculating content and deposit contributions in the area around the relevant facilities, we can determine the magnitude of the dusting.

Dispersion calculations of emissions to air are often used in connection with permit tests regarding emissions from existing or planned industrial activities.

We perform calculations of content subsidies and deposit subsidies for emissions from individual industries or industrial complexes. We also have extensive experience of performing complete environmental quality descriptions. Using scatter modeling, we can simulate different emission scenarios for combinations of different gases, particles, aerosols and odors from different types of sources.

The content contribution from industry, together with the local background content, is then compared with current environmental quality standards and environmental quality objectives. In this way, an assessment is made of potential exceedances caused by emissions from industry.

The air environment in cities can vary greatly depending on infrastructure and the often large number of emission sources. IVL offers several services in modeling air quality in urban environments. The models can be used, among other things, for simulation of various action strategies, such as rerouting of traffic, placement of noise barriers and more.

Emission sources that can be modeled with dispersion calculations vary from a single point source to all emissions associated with, for example, road traffic. We can calculate combinations of different emitted substances at the same time and the dispersion models also take into account chemical processes, such as ozone formation. We can also simulate houses and street spaces in 3D as well as wind flow and spread of pollutants with very high spatial and temporal resolution.

There are over 270,000 horses in urban environments. The proximity to stables and riding stables affects allergy sufferers, but also how the Planning and Building Act and the Environmental Code are applied.

The spread of horse allergens varies depending on the size of the horse farm, topography, plant zones and meteorology. After several years of measurements at trotting tracks and horse houses, IVL has developed emission factors for horse allergens, both level and time resolution.