AORN Sterilization 2

Question 1

Which biological indicator organism is used to verify the efficacy of ethylene oxide (EO) sterilization?

Accepted Answer

Bacillus atrophaeus

Answer

Bacillus atrophaeus spores are the standard biological indicator for ethylene oxide sterilization cycles.

Question 2

A surgical instrument with a lumened channel requires what minimum processing classification according to Spaulding?

Accepted Answer

Critical

Answer

Lumened instruments that contact sterile tissue or the vascular system are classified as critical items requiring sterilization.

Question 3

What is the recommended minimum free air space around packages in a steam sterilizer load?

Accepted Answer

Items should be loosely arranged with space between packs

Answer

AORN guidelines require loose arrangement with space between packs to allow adequate steam penetration and air removal.

Question 4

How long must ethylene oxide-sterilized items be aerated at room temperature before safe patient use?

Accepted Answer

Up to 12 days depending on material

Answer

EO aeration times vary by material composition — some items require up to 12 days at room temperature to off-gas to safe EO residual levels.

Question 5

Which sterilization method uses the lowest temperature and is therefore safest for heat-sensitive electronics?

Accepted Answer

Hydrogen peroxide plasma

Answer

Hydrogen peroxide gas plasma sterilizes at approximately 50°C, making it suitable for heat- and moisture-sensitive devices.

(AORN) Association of PeriOperative Registered Nurses Practice Test