I got trapped in a parking garage last Sunday. It was crazy. As you pull in, you get a ticket, the gate opens, then a garage door opens, and then you park. No big deal. I did my shopping (at the Trader Joe's on Clybourne) and when I went back to the garage (validated ticket in hand), there was a line of cars by the garage door. A cop came and spoke with me and told me that the door was jammed about three feet open. He lamented that it was the only exit and quipped, "Can you imagine if this were an emergency?" He then told me that managers were called and someone should be here any minute.
After about five minutes (I ate a newly-purchased piece of fruit), I decided to go see for myself. I knew that the garage door at my parents' house had an emergency pull cord to release the door from the chain. There was no such cord on this door. Though there was a sticker indicating that there should be a pull cord. Shady. And trying to just lift the door nearly gave me a hernia.
Another guy started poking around and commented to me that if we removed two bolts, we could disconnect the door from bracket which attached it to the chain. Seemed like a plausible idea. I told him so, and he returned with some pliers. He found some cinder blocks to stand on so that he could work. When he got the first one unscrewed, I lifted the door to take tension off the bolt so it could be removed. We repeated it for the second bolt and we were free.
All in all, it was only about a half hour event. And really, it was kind of fun being part of the door dismantling. No manager ever showed up. I hope they got fined; that emergency pull cord release is there for a reason!