Defining the day population data

For the night population, it was assumed that people were at home for the majority of the time-period. For the day population, you will assume that half of the people are at home, that 40 are at the local school, and that the remainder are at work outside the area.

Create a copy of the Night population folder, and name it Day population.

Adding the shape for the school

The school is a large building on the south-west outskirts of the village as shown.

Select the Day population folder, insert a Population rectangle, and draw the population shape on the GIS Input View. In the Study Tree, rename the population node to The school.

Setting the population values

Select the Day population folder, view the Grid, and select Population from the dropdown list to view the seven day populations in the Grid.

Set the values as shown in the table below:

Setting up the ignition source data

The pattern of ignition sources might be different for day and night, but for this tutorial you will define a single ignition source, to be used for both day and night. The ignition source is a flare located just inside the north-west corner of the site and to the north of the propane sphere, as shown.

Select the Ignitions folder in the Risk tab of the Study Tree, insert an

Ignition point and place it on the GIS View, then rename the node to Flare. Then open the dialog and set the input data as shown below.