When Performing Sterile Aseptic Procedures,the Nurse Must Create a Sterile

When performing sterile aseptic procedures,the nurse must create a sterile field.Which of the following are included in principles of surgical asepsis? (Select all that apply.)

A) All items used within a sterile field must be sterile.
B) A 5-cm border around the edges is considered unsterile.
C) If two sterile objects touch,they are both considered unsterile.
D) A sterile object or filed becomes contaminated by prolonged exposure to air.