The worst one is when you use a restroom somewhere and the lights have a 2-3 minute timer. You're sitting on the toilet and...total darkness.
You may have just mentioned the sit down challenging task
@Cc_windsurfer , was referring to in his post.
Occupancy sensor lights have their place. I have one in a laundry room that works great. It's common to enter and leave with hands full and nobody sits around in there for long.
I've worked in plenty of warehouse and production areas with them. I'm not impressed for those places. One 660,000 sq ft warehouse was retrofitted throughout the building. Each sensor ran about 1,000 sq ft section of lighting. Shutdown timers were about 90 seconds. I had 48 lift trucks and 50 rider jacks working in that building. I swear to God that I've been in nightclubs with less flashing lights than that warehouse.
Another side to that type of environment is sensor location. The sensors in the busy warehouse were about 30 feet up near the roof. They covered a big area of movement. Except. . . The product was floor stacked and often reached ceiling height. Nobody really thought about the sensors when they started stacking. When they put tall stacks right under the sensors, the whole zone would stay dark because sensor couldn't detect.
That job was never a cake walk. It was downright dumbsville when some big shot would roll through and ask for the lights to get turned on for their tour. (Probably wanted to show off their fancy lighting.) I'd have to send crews out into the warehouse just to restack product away from sensors.
Dang this topic. I had happily repressed the memory of that job until thinking about occupancy sensors.
I ran a crew in another facility that used a linked sensor setup to run aisles as zones. The zone lit from any entry point and stayed on long enough to get away. Shutdown timers were about five minutes after zone showed no action. That setup worked fairly well. Some of my guys would work a zone for hours and never light the next area. In theory, that's how occupancy sensors should work.
Design and setup can be done right and wrong.
The 40 X 40 space could be done with multiple sensors, high sensitivity, and long duration. You'd have to keep the birds and bats out of the place, otherwise the lights could go on and off all the time. I'd personally be fine with a light switch at entry points.
@Kozmic , is it just one entry point?