I've never seen more BS and misinformation in my professional life since Three Mile Island.
First, the explosion was in the turbine building from hydrogen. Actually, hydrogen is used as a coolant for the generator portion of the turbine generator. This first unit is a Boiling Water Reactor. The reactor containment is such that most of the RADIATION is most likely tritium which not as dangerous as fission products which are contained in the uranium dioxide fuel
rods. Heat from decaying fission products are what need to be cooled and are being done so with flooding of the reactor core in its reactor vessel. The other reactor is a mixed oxide core containing plutonium. This is a metal that does decay with an alpha particle that cannot penetrate a piece of paper. It's danger is from inhalation which is probably not even out of the system reactor core, but in the fuel pellets.
The first unit is 40 years old and is toast anyway.
Remember, news media wants to create SCARE so you will watch their channel so their ADVERTISERS can be seen. $$$$$
Bruce, BS, MS, Nuclear Engineering, University of Florida, Professional Engineer, Nuclear Engineering