Simplify the following text for a Grade 2 native English-speaking person.
Original: Exceptionally pure and gas-free caesium can be made by the thermal decomposition at 390 Â of caesium azide , which is produced from aqueous caesium sulfate and barium azide . In vacuum applications , caesium dichromate can be reacted with zirconium forming pure caesium metal without other gaseous products .
Simplified: The human body does not need caesium .