On the morning of November 21, 1980, a major fire broke out in the MGM Grand Hotel in Las Vegas, USA. When the fire broke out, there were more than 5,000 people in the hotel.
The fire spread quickly, and soon smoke filled the building. As there is no alarm device, the guest room did not detect the fire in time. Many people smelled the scorching odor, and only knew that there was a fire in the hotel after seeing heavy smoke or hearing the sound of knocking on the door, the sound of broken glass and the sound of helicopters. Some people were evacuated out of the building in time, while others were trapped in the building. Some passengers died because the stairwell door was locked and trapped upstairs. After receiving the police, the fire brigade mobilized more than 500 firefighters to put out the fire and rescue the fire. After more than two hours of hard work, the fire was put out.
In the end, the fire accident caused 84 deaths and more than 600 injuries. According to the investigation, the short circuit of the wires in the upper space of the suspended ceiling caused the fire. Here we noticed a detail: "Some passengers were killed because they were trapped upstairs because the stairwell door was locked."
As an escape door, why is it locked in an emergency and cannot escape? Is there a device that can ensure the safety of the property and meet the escape needs in an emergency? After the stampede accident in Sunderland, England in 1883, the British Parliament passed a bill requiring all public entertainment venues to install a "bar" on the safety escape door, regardless of whether the door lock is locked or not. When the pressure on "reaches a certain value, the door will open.
The so-called "horizontal bar" is what we often call escape push bar locks, which are widely used in emergency exits in airports, hotels, large shopping malls, hospitals, transportation hubs, securities, commercial office buildings, factories, municipal buildings, government agencies and other places.
The outer side of the escape push bar lock can be equipped with an outer handle. Under the premise of ensuring the safety of people in the building, the outer side can be safely locked, which has both anti-theft function and rapid evacuation in an emergency; the inner side can also be installed The siren, in an emergency, presses the push bar to trigger the alarm, which serves as a reminder to the people in the building to escape and to guide the location of the escape route. Among all the functions of the escape lock, when the inner side goes out, only one action of the push bar can be retracted to open the door.