Client:

Leading Medical Device Manufacturer (Confidential)

Objective:

To perform a comprehensive Dose Mapping Study to determine the uniformity and accuracy of gamma radiation doses throughout the product packaging during sterilization.

Background:

The client required regulatory compliance with ISO 11137-3 for terminal sterilization using gamma irradiation. The key goal was to ensure that all product units, regardless of location in the load, receive the validated minimum required dose and do not exceed the maximum dose limit.

Challenges:

• Complex product geometry

• Mixed material composition

• High-density packaging arrangement

• Tight deadlines to meet a product launch

Approach:

1. Preliminary Load Configuration Study:

   • Analyzed packaging, pallet layout, and material density.

   • Selected representative product load for the dose mapping exercise.

2. Dosimeter Placement:

   • Strategic placement of dosimeters at critical locations (corners, center, sides, top, bottom) inside product cartons and outer packaging.

3. Irradiation Process:

   • Carried out gamma irradiation using a Cobalt-60 source.

   • Recorded absorbed dose from dosimeters after exposure.

4. Data Analysis:

   • Evaluated the dose distribution ratio (Dmax/Dmin).

   • Verified that all points met the validated Sterility Assurance Level (SAL 10⁻⁶).

5. Documentation & Reporting:

   • Provided detailed mapping report, dose profile graph, and recommendations for routine processing.

   • Submitted validation file as per ISO/EN guidelines.

Results:

• All measured doses fell within the validated dose range.

• Dmax/Dmin ratio was within acceptable limits (<1.4).

• Identified optimal load configuration to maintain dose uniformity in future batches.

• Received regulatory clearance post-submission.

Benefits to Client:

• Ensured regulatory compliance

• Reduced risk of underdosing or overdosing

• Enabled consistent sterilization process

• Supported product launch timeline