I have a 'color filter' in one safelight that I use when I print RA-4 color.
It is dark greenish and I think is a mid 70's afga product. It is fed light by a 15w incandecscant bulb. I bounce it off of the white ceiling tile roof of the darkroom, so the distance to where I feed the roller processor is about 6'.
Mostly I use glow in the dark tape bits on the corners of stuff to orient myself after the white lights go out.
The safelight is just a dull glow if you look at it right after the white lights are doused, and helps you to figure which way you are turned.
After about 20-25 minutes under its illumination my eyes start to perceive the shape of things in the room, and maybe a hint of (false) colour. I have never had a problem with it flashing paper that has been exposed all as a bunch, and then is sitting around waiting for me to feed it it intot he roller processor. I have not tried a more definitive test of this safe light.
So in your basement, I would suggest getting set up with some glow in the dark bits, and set up a radio station you like to listen to. Relax, and after 25 minutes what do you see?
Is is likely to change if someone turns a car around on the street in front of your house, or if the uncovered basement window wells end up with snow in them on a clear winter night?
I play it safe when working with ra-4 paper or panchromatic films. I only got the green filter five years ago. My first 20 years of ep/2 and the ra4 printing were all in the dark until exposed paper was into a daylight processing tube.