Sure, but what are the odds they're using these rather than HD 3.5" disks purchased from whatever new old stock they've been able to source over the past 20-odd years?

3.5" floppies were still common while I was in college. I have distinct memories of copying a project to a floppy in my dorm room, popping the disk out, walking next door (literally next door in the dorms, not even going outside up or down stairs or anything), popping the disk into a team member's PC and the project being gone. We laughed it off and chucked the disk in the trash and got another. Project wasn't lost-lost since I had a copy on my hard disk. This was also the era of the 100MB Zip Drives, which I also had in my PC and thankfully all of our lab PCs had, too. That's what I normally used for all of my day-to-day file transfers of any real import. I still have my zip disks, but I seem to have lost my zip drive, so no idea if the disks still have any data on them.

We used to copy files three times, better onto three separate floppies

Yeah at the time. You would get the whole range of good/bad disks. Sometimes even between computers. May work just fine on one computer and not the next. It was not common but it wasnt totally rare either. Just sometimes would catch out out at silly times.

That they are still used in a critical infra item is a bit surprising. Getting new stock would be a major hassle.

I was on a school paper in high school and was taking photos on a "digital" camera that wrote to 3.5" floppies. Some of them are still with the (printed) copies of my articles I kept. I'll have to see if they survived.

This is probably my "I'm getting old" moment. Good lord.

Sony Mavica?

I think it was!

[delayed]

Wow, it's crazy how experiences differ! I've never encountered anything more unreliable than zip disks. Even burned CDs lost to the dreaded buffer couldn't compete with the failure rate of those things. Past me wishes I had your luck with them, they were super cool.

You had personal PCs but no network in a dorm?

I'm placing that comment between 1985 and 1993.

Nah. 83 is much too early for everyone having a pc in the dorm room, and well after 1993 for dorms often not having network.

Depends on the schools for networks. I attended a college that finished adding wired networks to their dorms in 2000 or so. It just wasn't a campus priority in the 90s, fewer students had computers back then. If it was a school with more money or an engineering school they got to it earlier, the rest added it when they added it.

Also depends on the environment. My dad used to repair the pre-PC computers: Amiga, Commodore, Atari, Spectrum, etc. I've had access to them before many others have even seen a computer. I've been given a really heavy, not-completely-broken and usable laptop before they became affordable for normal people.

People who grew up with or lived in the tech environment had access to lots of things.

I was at an engineering school 90-93 (WPI) and they didn't have network access in the freshman dorms. Maybe they had it in the newer ones.

That was more common than not, for years.

Until quite recently, my Dad had a Zip drive plugged into an ancient Pentium box (back when "Pentium" meant "successor to 486"). I don't know when it was last actually used, but it's LED had been on since the 90s.

I used to do floppy disk data recovery as a service for students at college. Roughly speaking, we helped one student out every three hours, out of 2,500 students, during busy hours. Based on the rates and hours, I think it would come out to something like 25% of the student body, each year, coming to us with a data loss incident involving floppy disks.

YMMV. I’m sure a lot of people were shoving these things into backpacks, and this was post-2000, so the quality of disks for sale was poorer than it was in the 90s and 80s.

3.5" disks were much much worse.

Do you know the reason why?

I am guessing a combination of tighter manufacturing tolerances, smaller sector sizes, and manufacturers over time cheaping out would contribute to decreased reliability of 3.5" disks. People also, as far as I remember, universally used sleeves for 5.25" disks, but almost never had cases for 3.5" disks.

On the other hand, 3.5" disks have higher magnetic coercivity, which makes them less susceptible to data loss from stray magnetic fields (e.g. nearby motors).

I don't think you needed cases for them though since they covered the magnetic disk with their own sliding door while on 5.25" disks they were exposed to the elements. I once spilled jelly all over a 5.25" disk and took it out of the sleeve, washed it off in the sink, and put it in a new sleeve and it still worked :)

HD floppies were much worse, both 1.44MB and 1.2MB. They are just much more susceptible to defects from wear and tear because of the shrunken sector size. DD 3.5" wasn't as bad.

and how many bits have rotted on those?

[delayed]

“Modern” disks were not that good though.