Considerations for Lead Shielding

All lead shielding requirements need to be determined by a certified professional radiation health physicist. The amount of lead shielding required must be calculated properly, depending on the source of radiation, the type of machine used and where it is located. The goal is to ensure that maximum radiation protection is achieved.

Here are some considerations to help understand what factors determine lead shield requirements for diagnostic imagining and radiation therapy:

Energy & Exposure:  The energy potential of the machine determines the lead shielding requirement—the higher the output of the machine, the higher the lead shielding required. The amount of exposure per week, month or year should be determined, as well as the maximum patient volume growth, as radiation is cumulative and overexposure causes biological damage on the cellular level. Check the local governing health and safety law and codes for current compliance requirements.

Orientation/Direction:  The primary beam target of all wall lead shielding should be calculated by a physicist, in relation to the direction where the radiation is aimed and will scatter.

Distance & Occupancy: The closer a partition is to the radiation/x-ray source, the higher the shielding requirement because radiation dissipates more as distance increases. A very important part in the calculation is the amount of time, per day, a surrounding room similar to the x-ray room will be occupied by personnel or public. The lead shielding on wall and floors should increase with the level of occupancy.

Type of material: Heavy density materials such as concrete, steel and plaster can shield radiation to some level. The type of construction material used for wall, partition and floor can reduce the requirement for lead shielding.