How long before a case can a table be set up and still considered sterile?

Should a table be covered?

Should you wear a mask and gown just to set up a table?

These are questions we hear a lot. I had been taught that a dry table could be covered and was considered sterile for 24 hours. A wet table would be considered sterile for 2 hours. I have heard many other things. I have even done many other things. As a traveler, I worked in a lot of hospitals, who all had their own way of doing things. At one place, we set up a tray and covered it so the call team had a tray set up in case of call-back. If there were no call-ins, we used it for the first case in the morning. Another place set a tray out (closed) with all the equipment in a bag. If we were called in, the ED RN would open and throw the tray (not set it up) to save time for us. Every hospital is different…and that is a problem. There is no consensus for the sterile tray in the cath lab.

I have been researching this subject, and have gone to ACC/SCAI for their consensus document. It is a thorough document, and covers a lot of subjects, but does not address the sterile tray setup. TJC has no clear consensus on the back table. The only groups that really address the tray issue are the AST (Association of Surgical Technologists), Infection Control professionals, AORN, and Interventional Radiologists. The conclusions I drew from this research follow.


  • All personnel must change into scrub attire upon arrival
  • Hair coverings are to be worn at all times
  • Masks are to be worn when an open tray is present
  • Sterile gowns and gloves are to be worn when participating in the sterile field (scrubbing the case)

Tray preparation

  • The back table should be prepared less than one (1) hour prior to the procedure; preferably immediately before the procedure begins
  • A table cover is not recommended. If the table must be covered, the drape should not extend over any edge of the table.
  • The tech preparing the table should wear a gown and gloves in order to maintain integrity of the sterile field
  • The table should be prepared inside the suite in which it is intended to be used. It should be monitored continuously to ensure there are no breaks in sterility
  • No patient other than the one for which the field is prepared should enter the suite with the sterile field, whether it is covered or not
  • A new table meant for a different procedure or patient cannot be prepared in a room that is currently being used for a procedure or patient

I agree with all these for several reasons. First, changing at the hospital. I don’t know how many places I’ve worked where I watched people in scrubs with scrub hats on (you KNOW they were in surgery) walk into the hospital after riding in their car or on a bus or train. Changing into scrubs at the hospital ensures that you don’t bring outside germs with you. Seriously. How often do you get your car seats cleaned? And how do you know what’s on the seats of that bus or train? (I worked in Boston and changed clothes immediately after arriving at home following a train ride!) Changing into hospital-laundered scrubs helps to ensure patient safety.

Hats and masks? Yes, you really should. We’ve learned a lot from COVID-19, and one thing is, when we breathe, we breathe out lots of germs. And hair really does have a tendency to fall out, even when you’re not balding.  It doesn’t hurt to wear a mask during a case, and it doesn’t hurt to wear a hat (or two…I worked in the 80’s and had 80’s hair). It really will protect the patient.

Sterile gown and gloves when you’re scrubbed in. Need I say more?

Now, about that table.

According to the Society of Interventional Radiology (SIR), the table should be set up no longer than 1 hour prior to the start of the procedure, and preferably immediately prior to the start. It is possible to do that; I worked at a facility who mandated that the tray was not opened until the patient was in the room. Now, come on, guys. Most of us can set up a tray in 5 minutes or less. This shouldn’t be a problem. SIR also recommends that the table not be covered. And if it is covered, the cover should not extend over the edges of the table. The Association of Surgical Technologists (AST) agrees with this part. Having said that, I have seen table covers that are designed to break in the center and pull off (takes two people) in a way that never leaves unsterile over sterile. I’m not recommending products…it’s easy to find on the internet.

SIR and AST also recommend that the team member setting up the tray wears a gown along with gloves, hat and mask. I must say I agree with this for everyone. I’ve done that for years personally, because I’m short and round and tend to bump the table when I’m setting up. If you’re short and round like me, PLEASE wear a gown! But even if you’re tall, and can reach across the table safely when setting up, remember that when you reach across the table your unsterile arm is over your sterile field. That’s a no-no. And that’s the reason I recommend wearing a gown for setup. I also understand that this may not happen for COVID-19 reasons, but please make that the only reason it doesn’t happen!

The table should be set up inside the lab where it will be used. I’ve seen places that set up tables and moved them from room to room (covered, of course). This should not be done, although I understand the concept of emergency and changes within the cath lab. One thing that certainly should never happen is for a patient to be in a room with a table that will be used, or even meant, for someone else. Not even if it is 2 COVID-19 patients. Again, AORN, SIR and AST agree on this one. And don’t set up tray 2 while patient 1 is still in the room. Just, don’t.

Okay. I’ve given my opinion on this subject, along with explanations of why I believe what I’m saying. And this is my opinion. And my opinion plus $5 will buy you a cup of coffee. But it’s not just my opinion. It’s also the opinion of people who know.


Association of Surgical Technologists. (2019, November 4). Guidelines for Best Practices for Establishing the Sterile Field in the Operating Room. Retrieved from

Chan, D., Downing, D., & Keough, C. et al. (2012, July 17). Joint Practice Guideline for Sterile Technique during Vascular and Interventional Radiology Procedures. Retrieved from Journal of Vascular and Interventional Radiology:

Recommended Practices Committee, ICT. (2005, March 25). AORNs Recommended Practices for Maintaining a Sterile Field. Retrieved from Infection Control Today: