Incidents of nosocomial or healthcare acquired infections (HAIs) and bacteria that have become resistant to antibiotics (“superbugs”) are a concern for U.S. FDA. These ongoing incidents have heightened FDA’s attention to manufacturers of reprocessed medical devices. Manufacturers need to design devices that can be reprocessed effectively after patient contact, validate that the devices can be reprocessed in the healthcare facility, and publish clear reprocessing procedures and instructions for use (IFU) that are easy for healthcare personnel to understand and follow.

FDA Guidance

Devices soiled with clinical contaminates.

FDA issued two key guidance documents that address critical recommendations for manufacturers: “Reprocessing Medical Devices in Health Care Settings: Validation Methods and Labeling” and “Class II Special Controls Guidance Document: Instrumentation for Clinical Multiplex Test Systems.”1,2 These valuable resources outline important cleaning considerations for manufacturers of reusable medical devices.

One key draft guidance document that specifically addresses critical human factors is “List of Highest Priority Devices for Human Factors Review.”3 This draft guidance is intended to assist medical device manufacturers in following appropriate human factors guidelines and usability engineering processes to maximize the likelihood that new medical devices will be safe after cleaning. Complex devices that have clear potential for serious harm resulting from user error need to be validated for human factors. Human factors data should be included in premarket submissions for these complex devices unless the submission does not involve any changes to users, user tasks, user interface, or use environments from those of the predicate devices.

Cleaning medical devices.

The ability to clean a medical device should not be an afterthought for manufacturers; they need to consider ease of cleaning in the initial device design and engineering discussions. FDA recommends incorporating features that effectively facilitate reprocessing (e.g., flush ports) when designing a medical device that will be cleaned in a healthcare environment. When cleaning is taken into account in the early design phase of device development, it can positively impact the ability for healthcare personnel to effectively clean the device, which will improve patient safety.

Six Criteria for Reprocessing Instructions

FDA outlines the following six criteria for manufacturers to follow when developing reprocessing instructions:

  1. Labeling should reflect the intended use of the device. Medical device manufacturers must provide reprocessing instructions that are consistent throughout each product line. Validation testing needs to reflect the design and intended use of the device by simulating the contaminants, procedure, and wait period between the medical procedure and reprocessing the device.
  2. Reprocessing instructions for reusable devices should advise users to thoroughly clean the device. All cleaning instructions must include the text description, explanation, and diagrams of proper disassembly, use of protective covers and sheaths, and any applicable flushing instructions.
  3. Reprocessing instructions should indicate the appropriate microbicidal process for the device. Reprocessing instructions must include disinfection or sterilization processes (depending on the Spaulding classification) of the device and the compatibility of the device with the microbicidal process.
  4. Reprocessing instructions should be technically feasible and include only devices and accessories that are legally marketed. All products, equipment, and accessories used to reprocess devices should be defined with part numbers and have appropriate FDA clearance. Any parameters and processes validated and specified in the IFUs must be easily performed in any health care facility.
  5. Reprocessing instructions should be comprehensive. Every step of the reprocessing instructions should be thoroughly defined and explained. This includes any special accessories needed to complete each cleaning step (including cleaning agents), disassembly, rinsing steps (including water quality), and reassembly.
  6. Reprocessing instructions should be understandable. All reprocessing steps must be specified in sequential order from initial processing through terminal processing. These instructions should be text descriptions and should include charts, diagrams, and videos when available.

Conducting In-Use or Human Factors Testing

Automated washing of medical devices.

Manufacturers must assess the ability of healthcare personnel to follow the IFUs. FDA recommends in-use testing or human factors testing to verify that the medical devices can be adequately cleaned after patient contact in a healthcare setting. First, the contaminants present in the healthcare facility should be understood. Next, the devices determined to have the greatest cleaning challenges should be subjected to the worst-case soil scenario (in some scenarios, this would be contamination by patient use).

Once the devices and contaminants have been determined, the manufacturer can conduct classroom training for the healthcare personnel. The purpose of the classroom exercise is to educate the trainees to appropriately clean the devices during in-use testing. IFUs and other training materials must be ready and available for the classroom training. During this exercise, the manufacturer can solicit feedback from the trainees about the ease of use of the IFUs. This exercise is significant because it shows the manufacturer exactly how the IFUs are being used in the healthcare setting. Depending on the feedback, the manufacturers may need to adjust the IFUs if there are any usability issues.

The technicians who are selected for training should work in central processing and should not have prior experience with the devices that are being assessed. An expert from the manufacturer needs to be present for the in-use testing to answer questions that arise during cleaning. A qualified moderator facilitates the initial discussion, leads the classroom training, administers a survey, and solicits feedback after the conclusion of the in-use testing.

There are three recommended methods to perform the in-use testing of a device that has been cleaned in a healthcare setting to comply with FDA guidance:

  1. The medical device manufacturer will observe a technician cleaning the medical device. After the cleaning process, the device will be sent to a third-party testing laboratory. The laboratory will extract the device using validated extraction methods and test the extractions for residuals specific to the device type and surgical procedure. Organism recovery may also be tested, and organisms identified, to ensure that no high-concern organisms remain viable.
  2. The medical device manufacturer will observe a technician cleaning the medical device as in the first method. However, employees from the third-party laboratory will extract the device at the healthcare facility after it has been cleaned using validated extraction methods. These extractions will be sent to the third party’s laboratory and tested for residuals specific to the device type and surgical procedure. Organism recovery may also be tested, and organisms identified, to ensure no high-concern organisms remain viable.
  3. The third method is specific to scope in-use testing. As in the other two methods, the medical device manufacturer will observe a technician cleaning and disinfecting the scope. Trained personnel will extract the scope using an endoscope culturing kit, and samples will be sent to a third-party laboratory for testing. Protein and total organic carbon (TOC) residuals may be tested as well as organism recovery to ensure that no high-concern organisms remain viable.


Human factors related to healthcare reprocessing of medical devices is a valuable component of product development for all medical devices. If reprocessing steps are performed incorrectly, or not at all, it could result in serious harm to the next patient. In-use, or human factors testing, is a powerful method to ensure that users can appropriately follow and perform all of the reprocessing steps. This is an integral part of preparing the device for regulatory submission. Proper reprocessing of medical devices will decrease hospital acquired infections and increase patient safety.


  1. Food and Drug Administration. 2015. Guidance for Industry and FDA Staff – Processing/Reprocessing Medical Devices in Health Care Settings: Validation Methods and Labeling. U.S. Department of Health and Human Services, Washington, DC.
  2. Food and Drug Administration. 2002. Class II Special Controls Guidance Document: Medical Washers and Medical Washer-Disinfectors; Guidance for the Medical Device Industry and FDA Review Staff. FDA. Infection Control Devices Branch. Division of Dental, Infection Control and General Hospital Devices. Office of Device Evaluation. Center for Devices and Radiological Health.
  3. Food and Drug Administration. 2016. Draft Guidance for Industry and FDA Staff – List of Highest Priority Devices for Human Factors Review. U.S. Department of Health and Human Services, Washington, DC.

This article was written by Emily Mitzel, M.S., consulting manager/senior scientist at Nelson Laboratories, Salt Lake City, UT. For more information, Click Here .