A transparent glass window with a thickness of at least 6 mm and a width of at least 8 cm and a height of not less than 100 cm in the door shall be allowed to see the ascendant upon arrival at the floor.
Lock the door so that the slot can not during the upward movement.
Ensure that the boom does not work until all doors have been closed tightly.
The possibility of opening the doors of the fire with a special key by specialists in emergency or maintenance
