I think it will be perfectly fine. In my (no so) darkroom I can see lots
of light under the door, and as far as the paper does not "see" it (I
don't know how express it, I just keep the sensible face of the paper
upwards: the light comes in from the floor) I never have had a problem.
Yes, I have made test exposures, no fogging.

Javier

One experiment is worth many expert opinions.

Even so, in many places, if you will work at night and have the house
lights off little preparation is needed.  What I've done at various
places where I had a darkroom is sit as you did but do so on a very
bright day with all of the house lights on (except the room I want
dark) and then try to find the source of each bit of light.  I would
then take some thick black plastic and cover that spot and repeat
until I didn't actually see anything.

What you are proposing to do will work fine unless you leave a whole
box of paper open and happen to be wrong.

The rule of thumb I remember is: If you can visually count your
fingers after 5 min, it's too light. There's another one about leaving
a quarter on a sheet of paper and seeing it's outline after
developing ....  but I don't remember this one.

In my experience if it is a lot darker than the safelights, I am OK. If
what you mean and what I mean by "a lot darker" is about the same.

My darkroom leaks somewhat under the door. But my darkroom is L shaped
and the door is at the far end, away from the enlarger and sink. I
cannot see the leak until I have accommodated for 5 minutes or so. I
have tested exposures of paper (not the "quarter test" but the one Kodak
specify), and I get no fogging of paper even with the safelights on.

I have done less exacting tests with film. Basically, I do not get
fogging of 400 speed or slower films. I never use faster film than that,
so I do not know what happens with those.

I was once in the darkroom of an astronomical observatory. That was
DARK! It had no windows, an "air lock" type door setup. You could not
see anything, and 20 minutes later you could still not see anything. You
could leave film "exposed" in there I imagine.

Even the loading area for Kodachrome at their Fair Lawn plant had a dim
green safelight. It was not usually on, but they turned it on for
trainees. You could not see anything except the light, so you knew which
way you were facing, but that was about all.

You surely do not need anything like these last two examples.

    Its an impossible question to answer without testing.
As a rule of thumb if you can see _any_ light once your eyes
become dark-adapted, its too much. It takes a minimum of
half an hour of darkness for eyes to reach maximum
senstivity. Often a room which appears to be completely dark
at first will prove to be surprizingly bright once your eyes
get used to it.
    Since the sensitivity of film or paper is boosted by
exposure to low-level light even small amounts can cause
slight fogging.

--
Richard Knoppow
Los Angeles, CA, USA
dickburk@ix.netcom.com