From the engineering point of view, the single door opening saves the shaft space. But because of hospital elevators need to transport beds, the width of the beds should be considered. For example, if a hospital bed is 0.8 meters width, two beds will be 1.6 meters width,so the width of elevator is at least 1.6 meters. If the elevator doors are opposite, the elevator shaft must be designed as 1.6+0.8+0.8 which is 3.2 meters width. While In the case of single opening, only 1.6+0.8 which is 2.4 meters space needs to be reserved in the elevator shaft because of the elevator doors can be folded.
From the point of view of nosocomial infection control requirements, not only the design of elevator doors, including other doors, are all required to consider the closed function. The closure of the opposite door is easy to lead to lax closure after a long time, while the single door opening only needs to set an "E" type structure to ensure tight closure.
Observe the door inside the hospital carefully , especially the door of the operating room, all open and close in one direction.Even if designed with two doors two opening, normally it only opens and closes one.
In correct situation,hospitals with good infection control, go through the front door to of elevator the back door should has its own air shower function.
The primary consideration in the architectural design of hospitals should be infection control principles, followed by other considerations.