Well, calm down.I will show you the details.It is my fault. I didnt tell you when the detector alarmed.The situation is that whether you measure or not the detector outside or in your hands will never alarm or displays something abnormal.It dosent alarm untill you throw it into the chamber, with the shutter opening. Certainly, when the shutter open,the cover of the chamber will not open because of some locks. I dont know whether you will be satisfied with my answer. And i will apologize for the former answer.