CAESIUM-137

About: 

• Caesium-137 (atomic mass 137) is a heavier, radioactive isotope of Caesium (Cs) whose most stable form is Cs-133. 
  
  
• Production: Cs-137 is most commonly produced as a by-product in fission reactions of uranium and plutonium in nuclear plants or nuclear explosions. It is, thus, part of the spent fuel. 
  
  
• Properties: 
  • Silvery white, soft, and malleable, Cs-137 is one of the very few metals that exist in liquid form at room temperature. 
    
    
  • Cs-137 has a half-life of about 30 years. It decays through the emission of beta particles and gamma rays. 
    
    
  
  
  
• Application: Cs-137 is used in a variety of measuring instruments in the construction and other industry. It is also used, as in ONGC’s case, in well-logging devices in the drilling industry for the characterisation of rocks. 
  
  
• Health effects: Very high exposure — an extremely rare occurrence — can result in an increased risk of cancer.