Sterilization Validation
and Dose Mapping
From paperwork to testing, we ensure your sterilization validation is complete, compliant, and hassle-free.
What Is a Sterilization Validation? Why Do We Do It?
Sterilization validation is the process of demonstrating that a sterilization method, such as gamma, e-beam, or X-ray radiation, reliably achieves the required sterility assurance level (SAL) for a given product. It involves a series of tests, controls, and documentation to ensure the effectiveness of the sterilization process.
In short – if a product is to be marketed and sold as sterile, a validation is the proof that this statement is accurate.
For radiation sterilization, validation follows standards like ISO 11137 (“Sterilization of Health Care Products—Radiation”) and includes establishing and verifying the minimum radiation dose required to achieve sterility while ensuring product safety and functionality.
For E-Beam Validations, Who Is Involved and What is the Process?
(e.g. the original equipment manufacturer (OEM) or contract manufacturer)
(e.g. NextBeam)
For E-Beam sterilization we recommend the below sequence of steps. This sequence is designed to help understand quantities critical to E-Beam processing, such as dose uniformity ratio (DUR), early in the validation process to better inform other steps (e.g. maximum dose establishment).
E-Beam VDmax Sterilization Timeline
Samples Required
- Dose Mapping
3 “shipper” boxes - Max Dose Irradiation
Customer-specified - Microbiology
46-51 units (no LAL) - Bacteriostasis / Fungistasis (B&F)
3-6 units (Re-use) - Bioburden Recovery
3-5 units - Lab Analysis
10 units - Bioburden Enumeration
3 lots of 10 units - Bacterial Endotoxin / LAL (if required)
3 lots of 3-10 units
Things to Understand and Keep in Mind When Planning an E-Beam VDmax Sterilization Validation
- Basic devices with actively managed projects should be completed within approximately 8 weeks
- We recommend dose mapping as a first step (provides most risk reduction with lowest cost)
- This is a joint project between the Customer, Irradiator, and Microbiology Lab: coordination will be required on a weekly if not daily basis to ensure that work can occur on time. Lack of coordination can quickly cause schedule slips.
What Does a Sterilization Validation Determine?
A sterilization validation defines the minimum dose (Dmin) required to achieve a selected Sterility Assurance Level (SAL), the maximum dose (Dmax) that the product can acceptably be exposed to, and the ratio (dose uniformity ratio, or DUR) between these two for a given processing configuration (a combination of specific beam geometry and specific product/packaging configuration). Process variance is also estimated.
If Dmin can be achieved in a certain processing configuration within a given DUR (e.g. with no part of the product receiving more than Dmax), then the product is production viable in E-Beam.
How Do I Get Started With a Validation at NextBeam?
Step 1
Contact us to discuss your individual needs. We will provide a quote for dose mapping and other validation services as needed.
Step 2
Complete a Sample Submission Form (SSF) and ship three shipper boxes of dunnage for dose mapping
Sterilization Validation FAQs
We recommend performing dose mapping before or in parallel with the sterilization validation. Given the results of dose mapping and bioburden enumeration, the minimum and maximum dose specifications can be selected for the product. If the sterilization dose is known (from bioburden enumeration) and combined with the range of doses observed in the product (from dose mapping) before max dose testing then it is possible to select a max dose specification that is high enough to ensure the product can be processed routinely within the required dose range. Setting the max dose before performing dose mapping introduces risk that the product cannot be irradiated between the sterilization dose and maximum acceptable dose specifications… In other words, specifying a max dose ahead of dose mapping and sterilization dose determination is effectively guessing at what it should be.
We view an 8-week timeframe as a reasonable, real world “aggressive” timeframe. This assumes regular coordination between parties and no major “gotchas” or “lost weeks” where parties fail to communicate or delay in sending test products / sharing technical information.
Sterilization is typically indicative of a validated process that is designed to assure that any pathogens are rendered harmless. Sterilization processes must be validated to ensure they achieve the required Sterility Assurance Level (SAL), typically 10-6 for medical devices, meaning a one-in-a-million chance of a viable organism remaining. “Bioreduction” or simply “Irradiation” terms are sometimes used for processes that either target less stringent SALs or are not validated at all. These products may not be advertised as “sterile.”
Typically speaking, only triplicate dose mapping would need to be repeated in this case. Depending on the regulatory requirements where the device is sold, as well as the device’s categorization (e.g. Class II / Class III) either documentation of the change, regulatory body notification, or regulatory body approval is required. Read our “Changing Sterilization Modalities and Sterilizers for Global Products” for more information.
This depends on the method selected. Most commonly, the VDmax method is used. Quantities required for VDmax are shown below:
Samples required | |
Dose Mapping | 3 “shipper” boxes |
Max Dose Irradiation | Customer-specified |
Microbiology | 46-51 units (no LAL) |
Bacteriostasis / Fungistasis (B&F) | 3-6 units (Re-use) |
Bioburden Recovery | 3-5 units |
Bioburden Enumeration | 3 lots of 10 units |
Bacterial Endotoxin / LAL (if required) | 3 lots of 3-10 units |
Product Sterility Analysis | 10 units |
Other validation methods (Method 1 and Method 2 are less commonly used methods) have different requirements.
Microbiology labs vary in the services that they provide, their expected turn times, and specialties. We are happy to make recommendations based on your specific needs – contact us today for a free consultation.
Yes, there are periodic validation requirements as outlined in ISO 11137 Parts 1 and 2. Typically manufacturers perform dose audits on a quarterly basis.
Dose audits have their own basic test protocols. Typically 10 unit-level samples are irradiated at a low dose and shipped to a microbiology lab. The microbiology lab performs the required test of sterility on the irradiated samples.
Yes, you can choose your lab! We are also happy to recommend labs: we have relationships with labs of various sizes / specialties. Depending on your needs and preferences we are happy to make a recommendation.
Contact us today for a custom quote and to address any questions you may have.
Generally speaking, NextBeam requires 3 shipper boxes full of dunnage product as well as a completed Sample Submission Form before dose mapping can begin.
We do not offer the microbiology lab services required for a sterilization validation. Instead, we work alongside our customer and their choice of lab to ensure that an efficient sterilization validation process is defined and that the project is completed in a timely fashion. When working on a validation, our goal is to support seamless and rapid communication between the Customer, Lab and NextBeam: more schedule/cost overruns are caused by insufficient communication than technical problems.
A sterile product must complete sterilization validation and dose mapping to establish parameters for routine processing. NextBeam can independently develop a protocol or use a customer-defined protocol for Dose Mapping.
For NextBeam to begin work, we just need a filled out Sample Submission Form (SSF), which you can download via the link in the section above.
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Have a question? Speak with a sterilization expert today, at your own convenience.
