English: Medical lock on decompression chamber. Used to transfer medical supplies and food into and out of the chamber while it is under pressure. The small volume allows quick and economical transfer of small items, as the gas lost has relatively small volume compared to the entry lock, which is big enough to transfer people. The door is locked by a 45 degree rotation. A safety interlock which prevents any rotation of the door while the lock is pressurised can be seen in the disengaged position, showing that it is safe to open the outer door. The gauge also shows that the pressure has been released.