Why is My Plate Glowing?: A Case Study
Over the years people have collected and held onto an array of antiques, including cutlery, tea sets, ornaments, serving ware and many more. But who would have thought a plate could harbour such harmful chemicals?
The plate was found at a market and could not be left behind. The green colour is a characteristic feature of ‘uranium glass’. Uranium glass reached the peak of its popularity in the mid-19th century for the yellow or green hue. Under an ultraviolet light, the uranium causes the glass to glow a bright green colour.
A UV light was used on the glass under fluorescent lighting and in a dark room and in both cases the plate lit up bright green (Fig. 1). This was a good indication that the glass contained uranium and that we should investigate further.
Figure 1: The use of a UV light on uranium glass (a) under flourescent lighting and (b) in a dark room.
A Thermo Scientific RadEye B20-ER Survey Meter was used to test the radiation levels (Fig. 2). The natural background radiation level for the room was 0.14uSv/hr, and this represents the average reading to be expected in any given area. The highest reading on the plate was 2.4uSv/h (approx. 150 times the natural background reading). The lowest reading was 1.97uSv/h, which is still high.
To put this into perspective, the radiation dose coming off the plate is equivalent to:
· HALF the dose rate you would receive having a dental X-Ray (2.40uSv/hr)
· Equivalent to the “Annual Natural Background Radiation” that a person receives during their everyday activities e.g. food/drinks, radon gas from the ground, cosmic rays from the stars, buildings and soil). (2.4 uSv/h)
Figure 2: The radiation levels from the uranium glass, with a maximum value of 2.4 uSv/h.
Therefore, we would not advise eating or serving from this plate. This goes to show you can never be too sure of your surroundings. If you have any antiques or items of concern, feel free to contact us on: 08 9321 2830 or