About 1800 km southwest of Cape Town, South Africa, USS "Norton Sound" launched three modified X-17A missiles armed with 1.7 kt W-25 nuclear warheads into the upper atmosphere, where high altitude nuclear explosions took place. Due to the South Atlantic Anomaly, the Van Allen radiation belt is closer to the Earth's surface at that location. The (extreme) altitude of the tests was chosen so as to prevent personnel involved in the test from being exposed to any ionizing radiation. Even with the very low threat of radiation exposure, precautions were taken to prevent radiological exposure. The task force commander and his staff had laid out a series of precautionary radiation safe measures to be followed in each stage of the operation. Even though the chance of exposure to radiation from these missiles was so minute, the safety measures were still carried out as directed by the commander by the crew of Task Force 88.