What Is Sterile Validation?

22Jun

Uniforms and Apparel

Products such as reusable cleanroom garments and other items must be manufactured, processed, and laundered according to strict specifications. To be considered “sterile,” a product or cleanroom environment must be free of microorganisms. Sterile products are categorized as either those that can be sterilized in a final container or terminally sterilized, and those that must rather be aseptically prepared.

Sterilization validation ensures manufactured products meet specifications per standards of the American National Standards Institute (ANSI), International Organization for Standardization (ISO), and U.S. Food & Drug Administration (FDA). Validating the processes that allow this to happen is essential. The procedures for the sterilization process and how the process is controlled and monitored are key aspects of validation.

Cleanroom Validation Process

Whether using sterilization methods such as moist heat, dry heat, gamma or electron radiation, filtration, UV, hydrogen peroxide, etc., a validation study must follow established procedures. It requires looking at sterility assurance level (SAL) or the probability a single unit that has been sterilized in fact remains nonsterile. There’s never a 0% chance a microorganism hasn’t survived, and one can’t prove all of them have been eliminated.

In general, a sterilization process must deliver an SAL of one in a million.

Sterility method validation also accounts for the principles of hazard analysis and critical control points (HACCP) compliance. Originally designed for promoting food safety, HACCP is now used in a wide range of industries. Its steps include:

  • Analyzing the process for potential issues and hazards.
  • Identifying where hazards may interfere with the workflow (critical control points).
  • Calculating the parameters (critical limits) to observe at each control point.
  • Creating a means to track and measure activity at each point.
  • Setting up monitoring procedures for correcting problems.
  • Establishing procedures to ensure devices function as intended.
  • Establishing a process ensuring accurate data are recorded and stored.

Cleanroom Validation Tests

Process quality assurance

Testing is required for the purpose of sterile validation. The organisms most resistant to sterilization are endospores. Considering a device with a known number of microorganisms of a known resistance to a sterilization process, one can run a test cycle using a range of media, including fibrous paper, suspensions on material surfaces, or self-contained test units.

For proper validation of sterilization, the basic principles considered are:

  • Installation Qualification (IQ): Equipment must be installed based on manufacturer’s specifications.
  • Operational Qualification (OQ): All critical control equipment and instrumentation operate within required parameters.
  • Performance Qualification (PQ): Sterilizing conditions (physical and microbiological) are achieved everywhere in the sterilization load.

To validate equipment, three or more test runs must demonstrate control and monitoring devices, alarms, and operation indicators are working. The process requires maintaining chamber pressure integrity and chamber vacuum (if applicable) as well. Testers must also employ written procedures that accurately reflect equipment function.

A Closer Look at Validation Testing

Sterility method validation requires looking at heat distribution and heat penetration. Analyzing heat distribution, starting with an empty chamber, helps identify heat distribution patterns and maximum and minimum cycle times and temperatures. Multiple thermocouples should be used throughout the chamber. Sterilization validation also requires testing temperature distribution for all loads in all container sizes used and documenting thermocouple position, slowest to heat/cool spots, and the temperature distribution profile for each chamber load configuration.

To assess heat penetration into the full sterilization load, the entire load must be in contact with steam. Within the product container, the lowest and highest temperature locations must be identified, along with the slowest and fastest to heat locations. Using the highest fill volume container with the slowest to heat solution, variables such as container size, design, and material, as well as fill volume and solution viscosity are considered. Tests should be performed with maximum and minimum load configurations.

Cleanroom Validation Products

doctor wearing a face mask and protective googles

Laboratories and other environments requiring cleanroom clothing and uniforms benefit from reusable garments. Those, like Prudential Cleanroom Services (PCS), which are Clean Green Certified by the TRSA, are most trusted to handle reusable cleanroom garments. This acknowledges they have improved water/energy efficiency and adopted best management processes in relation to reusing, reclaiming, and recycling resources. It also validates gamma radiation has achieved the appropriate SAL.

Find Validated Cleanroom Products at Prudential Cleanroom Services

At Prudential Cleanroom Services, we have seven ISO 9001:2008 certified garment processing facilities validated for sterile processing, each with an assigned backup facility. We employ specialized garment testing procedures to meet certification requirements and support the cleanliness of your facility. In addition to cleanroom laundry services, we also supply high-quality cleanroom apparel (sterile and non-sterile garments) with high-density, liquid- and bacteria-resistant fabrics. These are incorporated into face masks, shoe covers, and full cleanroom uniforms.

For more information, request your quote online or call 800-767-5536 today.