How long should items be aired for after undergoing ethylene oxide sterilisation?

• A. 24 hrs
• B. 6 hrs
• C. 12 hrs
• D. 48 hrs

Answer: (A)

The main idea is ensuring residues from ethylene oxide sterilisation are reduced to safe levels before items are handled. Ethylene oxide is a toxic gas, and its residues can irritate or harm staff if not properly removed. After sterilisation, items are placed in an aeration chamber where the gas and byproducts off-gas gradually. A typical, safe default aeration time is about 24 hours, which generally brings residue levels down to the occupational exposure limits used in healthcare settings while keeping workflow manageable. Shorter times (like 6 or 12 hours) may not consistently achieve those safe levels, and much longer times (such as 48 hours) aren’t usually necessary unless specific loads or conditions demand it.