You can also use "guide numbers" just like you'd use with flash.
If you know that the exposure five feet from a lamp is 1/30 at f/4 then for that film and shutter speed you have a guide number of 20 ~ f/stop times distance equals 20. Thus:
3.5 feet you need f/5.6
7 feet you need f/2.8
10 feet requires f/2
14 feet requires f/1.4
A single reading and a quick look around the room to see what lights are on and where they're located and you should be able to figure exposure anyplace in the room. In places like offices, drugstores, super markets, etc., lighting is pretty standardized. Know the lighting in one Walgreens and you'll be on target at all the other Walgreens stores. Probably CVS too. Target, Walmart, K-mart, same thing. Make up a cheat sheet and carry it with you, maybe tuck it under the meter in its case or tape it to the back of your camers..