Why do the hunter in the sound of thunder wear helmets?

In Ray Bradbury's short story "A Sound of Thunder," the hunters wear helmets primarily for safety and protection against the prehistoric environment they are visiting. The helmets are equipped with communication devices and other technological features that help ensure the hunters can navigate and survive in a dangerous, unfamiliar landscape filled with massive dinosaurs. Additionally, the helmets symbolize the advanced technology of time travel and the precautions taken to avoid altering the past.