X-ray Door Lead Equivalents Explained: 1mmPb, 2mmPb or 3mmPb?

Every lead-lined door specification mentions a value like 1.0mmPb, 2.0mmPb or 3.0mmPb. This is the thickness of pure lead sheet that provides the same attenuation as the shielding built into the door. Choosing the right value is a physics question, but a practical understanding helps buyers communicate with both physicists and suppliers.

The shielding requirement comes from the imaging equipment. Conventional radiography (DR) rooms typically need lower equivalents, CT rooms sit in the middle of the range, and DSA or interventional suites - where exposure times are long and the tube moves - often require the highest levels. The room designer or medical physicist calculates the required attenuation from workload, distance and occupancy of adjacent spaces.

Importantly, the door is only one part of a continuous shielded envelope. The wall behind it, the frame around it and the gap under and beside the leaf all need equivalent protection. This is why professional lead doors come with lead-lined frames and overlap details instead of a bare leaf in a standard frame.

Vision panels must match. A 2.0mmPb door fitted with a 1.0mmPb window creates a weak point exactly at eye level. Matched lead glass with a lined bezel closes this gap and should be ordered together with the door.

Buyers should also ask how the lead is built into the leaf. Quality manufacturers sandwich full lead sheets between steel layers so the shielding cannot be bypassed by cut-outs, hinges or windows without engineered details.

Documentation is essential for regulatory approval. Type-test certificates showing attenuation measurements, plus material declarations for the lead sheet, are routinely requested by hospital authorities and should be supplied with every shipment.

Fenghe supplies lead-lined swing and sliding doors from 1.0mmPb to 3.0mmPb with matching frames, lead glass and documentation packages for X-ray, CT, DR and DSA rooms.