2015/11/14 at 11:06 pm
Southern Hemisphere November Background Increase.
There was a general increase in background levels detected by multiple stations in the Southern Hemisphere, in early November. In local rain swab tests, trace amounts of Iodine-129 and Lead-210 where detected, plus Radon-220 and Radon-222 washout decay daughters. The live Radon monitor reached a peak of ~ 1.8 pCi/Lt on the 14th November, during the storm event.
November 2015 Multi Station Detailed Reports:
Alert Caloundra 3rd November 2015 – It was 42% above pre-Fukushima average level on the 3rd November. This is the first alert level since March 2015.
Note: This alert code system here, is not based on any official government alert system. It is one set up by the station operator to indicate significant local increases.
From previous testing, when we reach alert levels here, rain events can cause large radon washouts. We haven’t seen any studies on the heath effects of being exposed to very large Radon washouts. It is suggested, if possible, to stay out of the rain when we have local monitoring station alert levels, and if you do get wet, have a shower when you get home.
Day average background level chart,
Dunedin New Zealand Report 4th November – “What is going on? Levels here from 0.8 to 1.6 pico Curies per litre, and rising …” This is a live Radon monitor detection.
Caloundra 8th November 2015 – Conducting a maintenance check on the GammaScout Geiger counter that is used to collect the day average background here, to confirm that these recent local elevated November detections are not caused by equipment fault, or from dust contamination.
I did find a small white fleck of material on the mica window which I brushed off with a very soft brush. I also cleaned out the whole unit, plus cleaned around the location where GammaScout is located. I also checked all the circuitry for damage, and the possibility that an insect got fried in the high voltage circuit area. An insect short would cause circuit malfunction, and erroneous detections. It all checked out OK. The next data download on the 9th November may confirm if the background elevation was caused by dust contamination, or from the particle found on the mica window.
Caloundra 9th November 2015 – The 24hour chart for the 8th shows a drop in background around 8.30am, after the monitoring Geiger counter was cleaned. Unfortunately there was a significant change in wind direction at the time. Wind started coming from the South, where as before it was manly from the North.
Therefore it is not conclusive at this time, if the Geiger counter cleaning, or the wind change caused the significant drop in background levels, from a day average of 0.148 uSv/hr on the 7th to 0.133 uSv/hr on the 8th.
Cairns 9th November 2015 Report – “My readings in Cairns for yesterday also went up to 0.147 uSv/hr. Will keep an eye on it and will let you know of further development.”
Cairns 10th November 2015 Report – “The reading for Cairns yesterday increased further to 0.166 uSv/hr. The highest reading since Jan this year. I am charging the battery at the beginning of each month, so that should eliminate any problems with that. Will keep you informed about further development.”
Cairns is red in this chart and Caloundra is yellow.
Cairns 11th November 2015 Report – “Yesterdays reading was down to normal again at 0.125uSv/hr.”
Alert Caloundra 14th November 2015 – It was 43% above pre-Fukushima average level on the 14th November. There were a series of thunder storms that passed over the area, followed by heavy rain, that came from the South West in the evening. The local live monitors here showed elevated background levels for most of the day. When the storms passed over, the background level peaked.
Southern Hemisphere updates can be found here,
Disclaimer: This is an amateur volunteer run service. Human error can provide incorrect information, and equipment malfunction can produce false readings. Do not rely on, or take action upon information presented here, without further research.