Customers often ask how they can implement cleaning verification as part of their Quality Control Process for reprocessing Flexible and Semi Rigid Endoscopes.

Sterile processing professionals are expected to verify that they are able to clean, disinfect, and sterilize instruments using automatic cleaning equipment and manual cleaning processes according to the manufacturer’s instructions for use (IFU).

What the Standards Recommend On Cleaning Verification

AAMI ST 91 12.4.2 Cleaning verification

Cleaning verification of flexible and semi-rigid endoscopes should include: Visual inspection combined with other verification methods that allows the assessment of both external surfaces and internal housing and channels. ( ANSI/AAMI ST91:2015 Flexible and semi-rigid endoscope processing in health care facilities, p 39)

AORN “Guideline for processing flexible endoscopes” include the following

Manual cleaning of flexible endoscopes should be verified with cleaning verification tests when new endoscopes are purchased and at established intervals ( eg, after each use, daily). (2016 AORN Guideline for processing flexible endoscopes, XIII.f., p734).

Visual Inspection

Visual Inspection should be conducted to detect the presence of any residual soil. Inspection using magnification and additional illumination might identify residues more readily than the unaided eye. For internal channels of device, a video boroscope of an appropriate dimension (length and diameter) may be used to visually inspect the internal channels of some medical devices. 2015 AAMI ST 91 p39)

Although it is not a guarantee that decontamination from manual cleaning is complete, visual inspection can be considered a safety stop or “time out” to ensure the endoscope is visually clean before proceeding to the next step of high level disinfection. ( 2016 SGNA Standards of Infection Prevention in Reprocessing of Flexible Gastrointestinal Endoscopes, p18).


Cleaning verification tests for users


Real-time testing of endoscope lumens/elevator channel should be done immediately after manual cleaning so that any improperly cleaned devices are re-cleaned prior to High level disinfection.

To confirm the adequacy of manual cleaning, a rapid cleaning monitor (or rapid audit tool) for residual organic soil can be used prior to high-level disinfection. If the tool results are positive, this allows for the recleaning of the endoscope prior to disinfection. The frequency of the testing should be determined by the individual institutions ( 2016 Standards of Infection Prevention in Reprocessing of Flexible Gastrointestinal Endoscopes, p18-19)

AAMI ST 12.4.3 recommends establishing a reasonable benchmark. This is the level of cleaning that can be achieved consistently using specific soil markers relevant to devices used for patients.

Common Markers used include Protein, Carbohydrate, Hemoglobin (blood) and Adenosine triphosphate (ATP) (2015 AAMI ST91, p39)

Options of Chemical tests for residual soil markers

Protein or Hemoglobin detection by chemical reaction interpreted as a visible color change or a quantitative measure of residue (utilizing a color chart [semiquantitative] or photometric device). Samples may be collected by swabbing, flushing, or direct application of reagent. (2016 AORN,p735)

Detection of ATP by chemical reaction. Measurement of fluorescent light reported as a numeric value. Samples may be collected by swabbing or flushing. ( 2016 AORN,p 736)

Verification of Cleaning Equipment

Manufacturer’s written IFU should be consulted for recommendations of types and frequency of cleaning efficacy testing.

AAMI ST 91 12.4.4 states that testing the equipment upon installation, during routine use (daily) and on all cycles used, after repairs, and when changing to a new type of cleaning solution allows the user to verify its continued effectiveness. (2015 AAMI ST91, p40).


Key Take aways

Since there is no single method that has been established as a standard for cleaning verification, facilities should establish a multidisciplinary team to evaluate the need to implement a program for regular microbiologic surveillance of flexible endoscopes and mechanical processors. ( AORN 2016 Guidelines for Perioperative practice. Processing Flexible Endoscopes. XIII.g, p 741)

Your facility’s reprocessing program should include written procedures for monitoring training and adherence to the program, and documentation of equipment tests, processes, and quality monitors used during the reprocessing procedure. ( FDA Supplemental Measures to Enhance Duodenoscope Reprocessing: FDA Safety Communication) 


  1. ANSI/AAMI ST91:[2015] Flexible and semi-rigid endoscope processing in Health Care Facilities. 12.4.2; 12.4.3; 12.4.4; p. 39-40

  2. The Guideline for Processing Flexible Endoscopes. [ AORN 2016]. Section XIII.f. p18-19; p734- 736

  3. FDA Supplemental Measures to Enhance Duodenoscope Reprocessing: FDA Safety Communication