The BAS P and BAS U training is valid for five years from the date of issue. After five years, you need to undergo refresher training to continue working as a BAS P or BAS U. The reason for the five-year validity of the training is that it is important to ensure that coordinators have up-to-date knowledge and experience to identify and manage risks safely. The construction industry is constantly changing and evolving, and requiring refresher training ensures that coordinators have the latest knowledge and the best tools to protect health and safety on site.