Here we see a cut-away view of the Launcher Equipment Building. During a standard site access procedure, known as "pen & backout", you would open the personnel hatch at the top of the structure (which actually sits at ground level), install a connecting J-ladder assembly, then decend about 50 feet to the lowest level of the access shaft. Once there, you will pump open the lockpins that hold the door closed against any blast force, using a manual hydraulic hand pump, which takes about 100-150 strokes. Then you open the latch and slowly and carefully pull the huge blast door open; mind your step as you do so, as the amount of momentum generated by the door is not easily stopped. Several careless people have been severely injured in the past by getting in the way of the ponderous door. Another nuisance (or danger) lurks in the door operation: if the Environmental system inside is not balanced properly, the interior air pressure can either create a suction that will not allow you to pull the door open, or create an over-pressure that will blow the door open with suprising speed when unlatched.

Once the blast door is opened, you will obtain the Safing Key needed for any work in the Launcher Equipment Rooms, and perform various checks and inspections of the equipment in the LEB to ensure it is in proper working order. Then you proceed back to the surface and continue with the arduous task of penetrating the silo - now opening the Launcher Equipment Rooms (LERs).