Safely Remove external partitioned HDD

What is the correct method of safely-removing a multi-partitioned external HDD ?

My new external USB HDD has 3 partitions for data only. (1 Primary and 2 logical partitions)
J is Primary (partition)
K and L are logical (partitions)

I am used to safely-removing devices with single drive letter (partition), but I am concerned about losing data on a partition/drive I have not safely removed ... OR does Windows recognise the selected partion/drive is part of a device with other partitions ... and evaluate all drives/partitions on the device to determine ready for release ?
- yesterday I discovered new scanned image files can take some time (10+ seconds) to finish saving to an external device.

Thank you :)

Hi PSCO2007, thanks for your response :)

I have used "Quick" removal in the past.
- on a few occasions pulled the device and ended up with RAW file format.
- one time I was able to recover data (2 hours) but the second time I lost all data, the device formatting was toast. (Fixed with free MiniTool)
- three days ago I scanned (new A3 flatbed ) an A3 page to a thumb drive and it took a about 30 seconds after the scan, to complete the "save".
- the scanner is Avision -- high end, not a toy
- The image was not available in WinExp for about 30 seconds. I experimented for about 20 minutes.

My problem might be the rig is XP (all others are Win7) but the XP machine is central to my business.
- I have plans to ditch XP and install Win7 on the rig (bought the OS about 8 months ago)
- time ...

When Windows safely-remove baulks, Windows does not even hint at the problem.
- I have been using commercial USB Safely Remove which shows the drive label (Windows SR does not) and USB Safely Remove shows a report if the device is locked, and why.
- for stubborn devices I use free LockHunter ... I have tried several so called unlockers but LockHunter is, IMO, by far the most successful and stable.
- I tried using sync.exe from SystemInternals, it works, but is time consuming
The worst offenders of stubborn drives (i have found) are older devices. Don't ask me how old ... old is
- they don't get wrinkles as they age, they just play up at the most inconvenient time.

My major concern is safely removing a partitioned drive.
- in any safely-remove app only one drive can be selected for "release", but I want to be sure the other partitions/drives are also ready-for-release.