Variable Lead Thickness

The important balance in radiation protection is always balancing the radiation dose received and how much shielding is employed. While it is desirable for as much radiation shielding as possible and therefore allowing the minimum exposure to radiation, this is expensive, heavy and sometimes impractical.

What is Reasonable?

Typical balancing scenarios are:
• For a small transport container where a low surface dose rate must be achieved as the container is frequently handled, the mass must be kept low as the container is being lifted and carried.
• For a sharps enclosure positioned adjacent to an operator’s workstation the dose rate must be kept to a minimum and while the mass is not so critical the cost may be, especially if the shielding is to be applied over many sharps bins in a single department.

To help in striking this delicate balance Radi-tech designed products can be constructed with any thickness of lead. For SPECT applications thickness between 3 and 9mm are typical, for I-131 lead thickness between 6 and 12mm and for PET thickness from 30mm are commonly used. While thicker lead allows for lower surface dose rates the thickness of lead dictates the overall mass of the item and the cost.

The lead thickness can be specified at the point of order with maximum possible lead thickness and mass for each thickness shown on the product page and in the product operating manual. To help to easy identify the lead thickness a product can be loaded with the following key has been assigned:

SPECT                  6mm             Well suited for Tc-99m and Co-57 energies
SPECT+               12mm            Additional shielding for I-131 or very high activities of Tc-99m
PET                      30mm           Suited for moderate activity FDG
PET+                   50mm            Additional lead shielding for high activity FDG or high energy isotopes such as Zr-89