The system of radiological protection, including the ICRP documents, is required be as practical as possible and easy to understand. In this regard, this document needs to be revised so that its contents will be described more clearly. The emergency situations assume a various kinds of events. To address these situations, it is important to note the fact that the effects of an event may extends to a wide range and out-of-scenario events, such as an unexpected radiological release, may happen. Once an event occurs, an utmost effort is made to finalize the event in a safe manner. In the course of finalization, the optimization of protection in the radiological protection system is pursued while various data are being collected. To achieve the optimization, top priority should be given to the reduction of the maximum radiation dose as low as reasonably achievable, economic and social factors being taken into account. /Basic principles (a) h In order to avoid grossly inequitable outcomes of this optimization procedure, the process should be constrained, ch This paragraph should be changed to a description considering the reality that gby means of optimization, overall radiation doses should be reducedh. /Reference level It is essential to project the development and changes of an event as correctly as possible with an assistance of related experts including those in the field of radiological protection, and then, based on the projection, implement optimization based on the concept of ALARA. In other words, obtaining the maximum averted dose based on the concept of ALARA from the projected dose rather than setting a reference level and then implementing optimization so as not to exceed the reference level is desirable. In this respect, the concept of setting an action level is more realistic than setting a reference level. This draft states that reference levels should be selected in the range 20 to 100mSv/y. It is not useful than IAEA standards relating to particular protective actions. In addition, there is no clear definition between short-term and long-term protective measures. It should be noted that we can not control the radiation sources in case of emergency, it might be necessary to change reference levels flexibly considering the situation.