DecontaminationQuestion 9 of 100

An ultrasonic cleaner has just been filled with fresh solution at the start of the shift. Why must the unit be degassed before instruments are processed?

a.Dissolved air in fresh solution cushions the sound waves and prevents effective cavitation
b.Degassing raises the solution to the required thermal disinfection temperature
c.Degassing removes residual detergent from the previous shift
d.Degassing sterilizes the solution so instruments leave the unit sterile

Explanation

Fresh water holds dissolved gas that absorbs ultrasonic energy and dampens bubble formation, so the unit is run empty for several minutes to drive the gas out and restore full cavitation. Degassing is not a heating, rinsing, or sterilizing step. An ultrasonic cleaner never sterilizes; it is a cleaning device only.

Law Reference: AAMI ST79

Practice all 100 questions free — no signup required.

Related questions on this topic

Last reviewed: · editorial process

PrepPass Editorial Team · Verified against HSPA Certified Registered Central Service Technician (CRCST) Exam · How we review
Report