- Increasingly health monitors are on a network so that all the stats of a ward can be displayed at a central nursing station. The alternative is to turn the beeper really loud so that nurses at the station can hear it go off. In the case of (as an example) children, these monitors go off regularly - especially at night. The warning beeps are usually not a big deal but they do wake up both child and parent (whom often sleep at the hospital with the child). Oxygen Sat monitoring in particular has a high false-positive during regular monitoring on children. To ease the burden of parent, child and nurse these monitors are connected to a network and remotely monitored by nursing staff. This allows nurses to weed out false positives without waking everyone up.
- These networks should not be on the internet, I agree. But I can see low budgets (why run so many wires when one will work?!) and less-than-competent IT (also related to budgets) causing these networks to be connected to the internet.
I've seen air-gapped computers infested with malware. Portable storage devices can easily host malware. Air-gapped machines are more likely to have old, exploitable vulnerabilities, since they're not able to receive updates over the network and some people erroneously believe that being air-gapped makes them more "secure".
Edit: External media connectivity is typically used for updates. It's much more convenient to have a USB port that will use an off-the-shelf mass storage device than a JTAG and a custom programmer.
For something like a fetal heart monitor, which has been certified to work in exactly one configuration, why would you allow external media? Have an internal network, and lock down every device. If nurses want to have a computer to use for Facebook, it can be on a separate, non-medical network.
You'd allow external media because you need the data off the device somehow. Unfortunately, if the monitor uses a COTS operating system (doesn't matter which), that's one way in for malware. Unlike their military applications, air gaps in health care settings aren't there to protect confidentiality, but availability.
They're running Windows because that's what vendors design for. Nobody cares what the OS is. Nobody.
They're on the internet because it's convenient. The vendor has a support contract (so they can keep pulling money out of the hospital) which allows them to do software updates or maintenance without having to visit the site. Which they almost never do, anyway.
Are you being serious? If so, I'm just stunned that you're apparently of the opinion that medical data from recording devices should be sneakernetted around.
Why are these devices connected to a network, let alone the internet?
Why are these devices running windows? Don't get me wrong I run it too, but that doesn't mean it makes sense on something like this.