What is a common method for preventing internal contamination?

Using proper ventilation and respiratory protection is a common method for preventing internal contamination because it effectively minimizes the inhalation of radioactive particles or gases that may be present in the environment. Proper ventilation helps to dilute any potential airborne contaminants and reduce their concentration, while respiratory protection, such as masks or respirators, acts as a barrier to prevent the inhalation of harmful substances. This approach is crucial in environments where radioactive materials are handled or stored, where the risk of internal exposure can be significant.

The other options do not effectively address the prevention of internal contamination. Spending more time in radioactive areas increases the likelihood of exposure to harmful radiation without implementing any safety measures. Relying solely on dosimeters can monitor exposure levels but does not prevent contamination from occurring. Likewise, offering excessive personal freedoms in a work environment where radiation is present can lead to unsafe practices that increase the risk of contamination. Therefore, utilizing proper ventilation and respiratory protection is the most effective and proactive approach to safeguard against internal contamination.