The purpose of protection is to prevent harmful non-random effects and limit the probability of occurrence of random effects to an acceptable level. To achieve this goal, we must abide by the following principles.

（一）放射实践的正当化，放射性对健康有妨碍，为什么还要用放射性仪表呢？关键的原因是采用它可以带来巨大的效益，只有某一项放射实践带来年利益比付出的各种代价（对人群和环境的危害等）大得多时，才认为这项放射实践是正当的。

(1) The legitimation of radiation practice, radiation has hindered health, why use radioactive instruments? The key reason is that it can bring enormous benefits. Only when the annual benefits of a radiation practice are much greater than the costs (harm to people and the environment, etc.), can the practice be considered legitimate.

(二)放射防护的优化，为了避免不必要的照射，要花费一定的代价，采取防护措施，照射水平越低，花费就越大，因此要把放射实践带来的利益及花费的代价和达到的剂量水平综合起来考虑。求得一个优方案，也即利益大。花费的代价小，又能把剂量降到合理低的水平，并不是剂量水平越低越好。如果盲目地降低剂量，将得不偿失。

(2) The optimization of radiation protection, in order to avoid unnecessary irradiation, must pay a certain price, take protective measures, the lower the level of irradiation, the greater the cost. Therefore, the benefits and costs of radiation practice and the level of dose achieved should be taken into account. Find an optimal solution, that is, the greatest benefits. It is not the lower the dose level, the better the cost is the smallest and the dose can be reduced to a reasonable low level. If the dose is reduced blindly, it will not pay off.

（三）个人剂量当量限值

(3) Individual dose equivalent limits

在实施正当化、优化两项原则时，要同时保证个人所受的剂量不超过规定的限值。

In the implementation of the two principles of justification and optimization, it is necessary to ensure that the individual dose does not exceed the prescribed limit at the same time.

好了，今天的内容就先给大家介绍到这里了，收藏射线防护器材厂家官网：http://www.jnlzsb.com，可以了解更多详细信息！

Okay, today's content will be introduced to you first, collect radiation protection equipment manufacturers official website: http://www.jnlzsb.com, you can learn more details!