A FEW HANDY TERMS

1. MINIMUM DOSE: The minimum dose is defined as the amount of radiation required to achieve the effect desired. All portions of the product must absorb at least this amount of radiation for the process to be effective. MAXIMUM DOSE: The maximum dose is the amount of radiation that no part of the product should exceed, either because unwanted effects will occur, or because a regulatory limit applies. A FEW HANDY TERMS DOSE UNIFORMITY RATIO (DUR): This is the maximum dose received somewhere in the product divided by the minimum dose received somewhere in the product. It is sometimes referred to as the MAX/MIN Ratio, the Overdose Ratio, or simply U. Typical Minimum Dose Requirements (in kiloGrays) Inhibit Sprouting 0.05 Fruit Flies (Generic Quarantine) 0.15 Insects – Non-Fruit Flies (Generic Quarantine) 0.40 Prevention of Mold on Fruit 2.00 Shelf-Life Extension 1.50 Pathogen Reduction (Meat & Poultry) 1.50 Spice Sanitation 6.50 Sterilization (Medical Devices) 25.0 Sterilization (Food) 46.0 RADIATION DOSE: This is the amount of radiation energy absorbed in the product. This energy is converted to low-grade heat. The product itself does not become radioactive. The modern unit of measurement for radiation energy absorbed in use today is the Gray(Gy), which is equal to one joule per kilogram. Often used is the kiloGray(kGy), which is equal to 1,000 Grays. These replace older terms such as the Rad (Radiation Absorbed Dose). One Gray is equal to 100 Rads. AVERAGE BULK PRODUCT DENSITY: This is the average bulk density of the product in its processing configuration. This is defined as the total weight of the product stacked in the “carrier” to be irradiated, divided by the total volume that the product takes up in its stacking configuration. This includes the packaging material.