As an experiment I used a "daylight 5500k" spiral fluorescent, 100W equivalent, placed 8" from some cyanotype (traditional two part formula, not M. Ware's type II) and a 4x5 negative. After one hour I was just beginning to get a recognizable exposure.
So, this suggests to me that for the GE branded 5500k bulb, its UV coating was pretty good. I would have little concern about using such a bulb at 6 to 8 feet in the overhead fixture for the 10 to 20 minutes I'd need to mix and coat cyanotype sheets.
That said, I still plan to test for fogging by mixing the chem under my standard safelight and coat one sheet. The put that sheet in a dark place, switch bulbs and coat a second sheet. Both would dry in the same dark place for the same amount of time (minus the time to change lights and coat the second sheet). Then I'd do something akin to the standard safelight fogging test for photo paper. Use a large, light proof object, a half dollar perhaps. Tearing each sheet into four or six pieces I could test in 15 or 10 minute intervals with the fluorescent room lights on with exposures upto one hour.
With the Mark I eyeball, I expect to see little or no fogging at up to 30 minutes with either paper. A reflection densitometer might tell a slightly different story though. Except that I've never used a reflection densitometer to look at watercolor paper so no idea of the paper texture will foul it up.
Should be interesting none-the-less.