Precautionary actions are taken in order to prevent something dangerous or unpleasant from happening.
The local administration says the curfew is a precautionary measure.
地方当局说这次宵禁是一种预防性措施。
the process of taking precautionary steps to ensure that no one will be blamed if something goes wrong.
采取预防性措施,确保如果出现了问题没人会被问责。