Does somebody know the specification and other details about fluorescent lighting used in International Space Station before LEDs were installed there? Maybe NASA presented some publications on this topic, but they are hard to find in the wake of new LED lighting news.

I think I remember reading somewhere (I don't remember where) that they were standard F40T12 on magnetic RS. They had packed an extra case or so but they ran out of lamps and there were quite a few EOL ones. Then came LED.

Ok, I had a look around on the Web, and can get lots of information on the new LED, of course, but very scarcely on the old fluorescent. From the pictures, I guess they're not F40, but they look more like F15Tsomething. I have found that most of the fixtures contain two lamps that alternate operation on every startup to elongate the time between relampings. I also found that it would have been too difficult/expensive to design LED tubes to fit in the existing fixtures.

It seems that F20T12 tubes were used:
http://spacearchitect.org/pubs/AIAA-2013-3515.pdf
ttps://spacegrant.carthage.edu/ojs/index.php/wsc/article/download/126/126

Makes sense. Thanks.