How does ventilation contribute to radiation safety?

Ventilation is a critical component of radiation safety as it helps dilute radioactive aerosols in the air. When working in environments where radioactive materials may be present, proper ventilation systems can significantly reduce the concentration of these materials in the air. This process minimizes the risk of inhalation by workers and thus decreases their overall exposure to radiation. By ensuring that potentially harmful airborne particles are dispersed, ventilation serves as a practical measure to maintain safer working conditions in areas where radioactive materials might be handled.

The other options do not accurately describe the role of ventilation. It does not completely block radioactive materials (the first choice), nor does it increase radiation exposure (the second choice). Additionally, while ventilation plays a role in controlling contamination levels, it does not directly prevent contamination itself (the fourth choice). Therefore, the correct answer reflects ventilation's specific function of diluting radioactive aerosols to enhance safety.