The Biowash Weapons System was developed to clear structures of all life, but to leave the structures themselves unharmed. This is achieved through the use of a high-yield nuclear device that uses certain radioactive materials and shielding devices. Through these devices most of the energy from the blast is released as alpha radiation. This radiation has a short lifespan, but is deadly to all organic lifeforms. It is also not absorbed by non-organic materials, thus there is no lasting radioactivity in the blast area.