Uses and application of radiation in radioactive dating
The energy source for this device was a rod of plutonium-238 weighing approximately 2.5 kilograms and providing a thermal power of approximately 1250W.
Therefore the irradiated substance is sterile but NOT radioactive.
A chest x-ray can be used to diagnose lung diseases such as pneumonia and mammograms use x-rays to screen for breast cancer.
X-rays are also used in a type of computed tomography, more commonly known as a CT scan.
Smoke entering the detector blocks some of the alpha particles, lowering the current, and triggering the alarm.
Many camping lantern mantles used to contain thorium (alpha emitter with a long half-life see decay series). This practice has been stopped but old stock may still be around.