Why should the edges of a sterile field or container be considered contaminated?

The edges of a sterile field or container are considered contaminated primarily because they can come into contact with non-sterile objects, which enhances their susceptibility to contamination. The outer edges serve as a boundary for the sterile area, and when these edges are touched or come into contact with non-sterile surfaces or materials, they can pick up pathogens or contaminants. This principle is rooted in the fundamental practices of infection control in medical and laboratory settings, ensuring that the integrity of the sterile field is maintained to prevent infections or contamination during procedures.

While factors like visibility and overall safety are important considerations in maintaining a sterile environment, the primary reason for treating the edges as contaminated is their direct exposure to potential sources of contamination. Therefore, careful handling of the edges is crucial to preserving the sterility of the contents within the field or container.