Detonated in a tunnel beneath Rainier Mesa with a yield of 1.7 kilotons, the Rainier test proved that nuclear weapons could be tested underground without releasing radioactive fallout into the atmosphere. The success reshaped American and Soviet testing practices, eventually underpinning the 1963 Limited Test Ban Treaty's allowance for continued underground testing while banning atmospheric detonations.
Detonated in a tunnel beneath Rainier Mesa with a yield of 1.7 kilotons, the Rainier test proved that nuclear weapons could be tested underground without releasing radioactive fallout into the atmosphere. The success reshaped American and Soviet testing practices, eventually underpinning the 1963 Limited Test Ban Treaty's allowance for continued underground testing while banning atmospheric detonations.