Class 7 are radioactive materials categorized into one of three categories depending on the severity of the danger of the radioactive source.
There are various types of radiation. Alpha particles are relatively low and heavy. They have a low penetrating power and can be stopped with a sheet of paper. Beta particles are fast and light and have medium penetrating power. They can be stopped by a sheet of aluminium or plastic. Gamma rays are waves, not particles, and have a high penetrating power. It takes a
آی-ویدئو