- Background Radiation Readings at Watauga Skies Observatory in uR/hr -

The Average Natural Background Radiation for Fort Worth, Texas area is 68.7 mR per year / 7.8 uR per hour.
Radiation Monitor #1: Black Cat Systems GM-45.

- Background Radiation Readings in Counts per minute (CPM) -
Chart updates automatically every 5 minutes.

The Eberline monitor uses a sensitive NaI probe to show highly detailed background gamma radiation data.
Radiation Monitor #2: Eberline RM-19. Probe: Bicron NaI.

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NEW! - 10/03/2011 - Why are readings typically highest in late morning hours, and lowest during early afternoon?

Studies show it is normal for the background gamma radiation levels to be highest in late morning hours, peaking in the early morning hours and lower in the early afternoon hours. This is often quite apparent on the observatory's sensitive RM-19 background radiation monitor!

The daily diurnal pattern of natural gamma radiation is mainly due to Radon daughters, caused by the radioactive decay of Radon combined with meteorological conditions.

It is important to note that sharp temporarily increases in gamma radiation are caused by the atmospheric sweeping action of rain.