Uses of Nuclear Radiation

Academic Applications - click here

Industrial Applications - click here

Medical Applications - click here

Other Applications - click here

Short half life

Tracers in industry - detecting leaks in pipes 

Tracers in botony experiments - e.g. phosphorus 32 is a beta emitter - taken up by the plant - can be detected outside the plant as beta penetrates thin plant structures easily - half life of 14 days makes it ideal for this.

Short half life

Medical tracer - used with gamma camera  

Tracers in industry - detecting routes of underground rivers and streams 

Short half life

Medical tracer - PET Scanning 

Long half life

Dating of rocks using Uranium-238/lead ratios 

Smoke detectors 

Gas lamp mantles 

Nuclear batteries  

Long half life

Thickness control of very thin metal sheets, paper or cardboard in manufacturing and industry 

C-14 dating 

Emergency sign lighting 

Long half life

High activity - radiotherapy  

High activity - sterilisation of medical surgical instruments 

High activity - irradiation of food to kill bacteria and prolong shelf life 

Thickness control of metal sheets (when too thick for beta) in manufacturing and industry 

Checking welds 

Other Applications

Nuclear Batteries

The Apollo Moon missions used a radioisotope thermal generator (RTG). The NASA designation for the devices that powered the Apollo Lunar Surface Experiments Package (ALSEP) for missions 12, 14, 15, 16, and 17 was SNAP-27 (Systems for Nuclear Auxiliary Power model number 27). 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. Plutonium-238 is a non-fissile isotope of plutonium that decays by alpha particle emission with essentially zero associated gamma emissions.

Smoke Detectors

Some smoke detectors contain a small amount of Americium-241, an alpha emitter (and low energy gamma emitter) with a half life of 460 years. It consists of an ionisation chamber linked to a simple electronic alarm circuit The Americium ionises the air between the plates, causing a current to flow. Smoke entering the detector blocks some of the alpha particles, lowering the current, and triggering the alarm.

Gas Lamp Mantles

Many camping lantern mantles used to contain thorium (alpha emitter with a long half-life see decay series). It apparently improved the flame. This practice has been stopped but old stock may still be around.

Emergency Exit Sign Lighting

During a fire, it's necessary to make sure that emergency exit signs remain illuminated, even if the power goes out. Some signs have a battery-powered light. Others have used tritium, a beta-emitting isotope of hydrogen, with a half-life of 12.3 years.

'Glow In The Dark' Watches 

All radium dial watches should be disposed of properly. Above is a demonstration of the radioactivity from a radium-containing 1950's Timex watch dial, using Geiger counter.

They also use tritium, see emergency exit signs above.

Vaseline Glass

Vaseline Glass is a particular color of yellow-green glass that is made by adding 2% Uranium Dioxide to the ingredients when the glass formula is made. The addition of the Uranium Dioxide makes the glass color yellow-green. It glows under ultraviolet rays

'Glow In The Dark' Clock Hands

Radium was painted on the hands of clocks, so they would glow in the dark. The radium was painted by women, who had the bad habit of licking the brush tips to form them, ingesting the radium. This resulted in illness. See the MIT research document: Radium Dial Painting and Its Tragic Consequences


LOJ (February 2001) - revised March 2021