229
This is a pretty good some up of the difference between things as they appear to be and things as they really are.
(hexbear.net)
I suspect a lot of people have difficulty recognizing that what they believe about the world may not be representative of how the world actually behaves. I certainly do, frequently.
Like with politics, people think they need to go vote and march and stuff to effect change, but if you're willing to accept the idea that there are limits to your ability to perceive the world and your perceptions are misleading, you can pretty reliably go and see that isn't true.
You can also decipher deeper realities like you can basically put whatever you want on flat bread, or that you dadskf;'akse'wfaegqrwt;'lj'a fuck my brain. I'm asd I'm not sure what I was trying to say.
Fail open means that fire code requires an unobstructed path of egress; You can't be locked in a building in an emergency. So mag locks are powered all the time in order to maintain the lock and then you remove power to open the door. This way if power goes out the door opens. In most major Corporate buildings, if you go into the fire panel room, you will find a relay that can simply be pulled out and will remove power to every maglock in the area. Or you can pull the fire alarm, cut the power, etc. Most big buildings also have a little lockbox aka a knoxbox outside their front door with a set of keys inside and some have a switch inside to kill the locks as well. They do have tamper switches though.
I can't remember using a magnet to neutralize a maglock, but I wanted to.๐ It would have to be a big one and honestly it would be easier to just slap something with a bit of thickness on the maglock when the door is open to prevent it from getting a solid "seal'. It'll give the appearance of being locked, but a good yank will let the door open right up. Often you can also just slide a piece of paper on a coat hanger between double doors or under a door to trip the PIR (passive infrared) sensor used to auto-open for people exiting. It shouldn't work, but those PIR are cheap as hell and often very oversensitive.
You can also spray a condensed gas through a door with a PIR on the other side. Only really secure building I worked in was for one of those Billy Budd type people who were really good at some niche technical thing and just hired enough people to be able to focus on the part that they found fun. His shop was in a squat brick building with steel doors that you had to press a button on the inside to open. There were well built steel edges to the door so that a hangar or some other means of attack could not be slipped around.
Yes! It wasn't consistent, but we were able to get that working with canned air a few times. Double doors worked best where you could get closer to the PIR above the doors. Holding the can upside down worked best, iirc.
Awesome to hear this actually working! I wonder if holding it upside down works best bc it grabs the coldest fraction of gas and causes the biggest temperature differential for the PIR?
That's my thinking. Most of the PIR aren't very impressive and they're just looking for that temperature change, it doesn't matter which direction. I actually wonder if maybe the paper trick works when it does because it moves the air flow from air conditioning around.
Not a clue tbh, the maglock uses an a pretty strong electromagnet on one side, metal plate on the other. Not sure what it would take to interfere enough once they're seated properly. Preventing that is your best bet and is often their downfall.