I graduated from the Institute of Physics and Technology. But I was more involved in programming, so I'm interested in taking becquerels (ddecays per second) and converting them to bytes (1 byte = 8 bits) for better understanding. Becquerels are too abstract.
Punched paper cards were once used, with a capacity of 80 bytes (80 characters, or a text line on the screen). I used these punched cards as sheets of paper for notes, but not as real storage use, because I used floppy disks (5 inches, later 3.5 inches). The radioactivity of natural potassium is 30 bytes; this is the fraction of a punched card. The proportion of radioactive potassium in natural potassium is small. If you had only radioactive potassium, its activity would be comparable to the capacity of a floppy disk of 360 kilobytes or more.
As you know, the capacity of a DVD is 4.6 gigabytes, or 4.6 billion bytes. I worked for a publishing house that had been in business since 1993 and initially used floppy disks, then CD-ROMs from 1996, and DVDs from 2003 to 2013. Later, the need for hard drives disappeared.
For comparison, the radioactivity of iodine-131 is 4.6⋅1015 Bq per gram, equivalent to a million DVDs or thousands of terabyte hard drives. In the first days after the Chernobyl accident, this background radiation circled the globe several times over, but quickly decayed.
Radiation can be caused by large amounts of a weakly radioactive substance (such as potassium) or dust from a highly radioactive substance (such as iodine), whose activity is comparable to terabytes or more.