Reading here
Plume and position
Air sample
Meteorology
Override (use the Information Board values)
Blank = Open-Meteo. Values entered here replace it until cleared.
Forecast (next hours)
Time and test position
Testing / desk use
Exercise time = phone clock + offset, so the plume develops in real time while you test (e.g. set 09:50 to watch the release start). Negative values go back. The offset is remembered on this phone until cleared. A test position replaces GPS until cleared.
Centre line now (for the umpire)
Basis
The meter needle is on a log scale from 0.00005 to 0.1 mSv/h; the red band is above 0.01 mSv/h. The map shows the plume to 2.5 standard deviations either side of the centre line. Map data © OpenStreetMap contributors.
RASCAL 4.3.4, Exercise DELTA best-estimate case D. The release is a containment bypass via 1 RIS 064 VP from 09:55, through DVK (iodine filters on) to the 65 m stack. The source is failed-fuel coolant, I-131 eq. 7.7E10 Bq/m³, at an assumed 70 m³/h.
Centre-line values come from RASCAL runs for each stability class, scaled by wind speed. Beyond 5 km they are extended along the 3–5 km slope. The lateral fall-off is Gaussian (Briggs open country), wider for gamma from the elevated plume. The release falls with time as the bypass drains the RCP.
Air samples follow KFG-EG-010 Rev 4: iodine counts give the adult thyroid committed dose rate (factor 3.8); particulate counts give the committed effective dose rate (factor 0.025).
Open-Meteo weather is a model and can differ from the Koeberg mast. If it does not match the Information Board, override it. These are exercise cues, not measurements.