Back in the Olden Days, whenever there was a lead-lined door, we scheduled a closer cover that was lined with lead, in addition to other hardware with lead which protected the holes through the door. The frames were also lead-lined (as well as the walls, which were not my bailiwick). It was all a little mysterious to me, but the objective was obviously to prevent radiation from passing through the door opening when imaging equipment was in use.
Last week I stumbled upon some information about lead-lined door closer covers that I had not seen before…a letter from LCN stating that the lead-lined covers were being discontinued. Attached to LCN’s letter is some information from the National Council on Radiation Protection and Measurements (NCRP). This states that lead-lined closer covers are not needed, because the steel fasteners filling the holes through the door (and the lead) do not result in significant radiation leaks; the steel fasteners generally attenuate the radiation equally or more effectively than the lead. Interesting, right?
I haven’t found a great resource on lead in doors, that would help us to know what to consider when specifying lead-lined doors, frames, and hardware. I’d love to compile some of this information for future reference.
If you have experience with lead-lined doors, please share your insight in the reply box!
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I have had many times Lead-Lined doors and the only hardware that I do Lead lined is the lock, the Rose/Escutcheon needs to be lead lined since the Function holes are bigger in size, sometimes the Pivots are lead lined as well but usually not, I also noticed most of the time the lead lined doors will not have a closer, it will either be a manual door without a closer or it will have an Automatic Operator.
Usually, when supplying a job with Lead Lined openings these are the doors they need first since the room has to be tested for Radiation Leaks and I never had a problem when having a closer without a lead-lined cover.
I would very appreciate a post about all the requirements for lead-lined doors.
As far as determining the amount of lead for an assembly (door/frame/hardware) you have to check the spec for the engineer’s determined required thickness based upon the equipment in the room. Usually I’ve seen 1/16″ lead lining for wood doors in hollow metal frames (hardly any for hollow metal doors). for a 1/16″ thickness I believe most wood door manufacturers will place one layer of 1/32″ lead under each veneer making them a total of 1/16″ thickness. So with the small screw holes into only one sheet of half the protection and then the hole being filled with another dense metal it will provide enough shielding to make a lead lined closer cover or additional shielding moot. Same with lead lined locks. If the shielding requirement is low enough the lock body itself blocks enough of the radiation that the lock won’t need the lead lining. Another fun note frames have different lead lining profile based on if the door swings into the room versus out of the room. Only required to overlap the lead to make sure no gaps so the entire frame profile doesn’t need lining, only the face to the stop to overlap with the door’s lining.
I had a job years ago adding intermediate pivots to an existing lead lined door. They wanted surface applied pivots so we brought up the issues of drilling thru the lead. Their Radiologist stated that 1/4″ hole being filled with a steel thru-bolt would not significantly affect the rating so it was OK to install.
Always a learning day.
I have inspected hospitals and clinics that have radiology rooms/departments and have been aware of the lead backed wallboard, also the ferrous metal and radio frequency shielding issues for MRI rooms, never though about the doors and door hardware on these uses.
I’ve heard the same thing about the fasteners being equal to the lead that it has penetrated.
I haven’t provided lead-lined hardware for lead-lined doors in years and have not had one call back/issue. Either they haven’t been testing the openings after installation or the fasteners really are better than or equal to the lead.
Wrestling with lead-lined doors was one of my least favorite tasks when I worked in the hospital.
We never had any lead-lined closer covers, but we did make mortise pocket liners out of thin sheets of lead for standard mortise locksets and mortise auxiliary deadbolts.
As a technical architect that specialized in healthcare facility planning and design for many years, I was usually the person called on when it came time to detail or specify lead lined doors and frames (as well as walls, and anything else that required shielding). I do not remember every having to line a closer. One of the sources I used for information was Ray-Bar Engineering. I just looked at their website (https://www.raybar.com/radiation-shielded-doors/accessories2)and see reference to lead lined lock sets, but nothing about closers.
One thing to keep in mind when shielding imaging rooms is that lead need only extend to 7′ above the floor. Since most doors in healthcare facilities are 7′ high, the closer is near the top of the lead.
If however, you are shielding a therapy room where there are gamma rays and other forms of high energy radiation, then all surfaces (walls, floor, and ceiling) may be shielded. In those types of rooms the doors are specially fabricated, and if there is a closer, it’s likely shielded in some manner.
This may be helpful from the Lead Industries Assoc. https://innovativebiomedical.com/wp-content/uploads/2012/03/radiation_shielding-lead-etc..pdf
Interesting, I too would like more information. I am a locksmith at a Hospital and I handle a lot of the door work.
At my previous employment we were told that radiation waves do not reach to 7’0″ which is the typical height of the door, therefore we stopped lead lining the closer covers. Of course I do not know where the information came from.
When scheduling lead lined doors check with the manufacturer where the lead is located in the door. This is important to know when scheduling hardware. I will always schedule kickplates with adhesive instead of fasteners. When scheduling mortise locks at lead lined doors the lock pocket will be larger than usual.
Pivots or continuous hinges should be used with lead lined doors because of the weight. Do not use standard butts.
When scheduling lead lined frames I will state where the lead is to be installed on the frame, either the wide or narrow side of the unequal rabbet frame.
There are special lite kits so check with your door manufacturer.
Allow for the lead lining at the jamb depth, typically the wall types will not note the make up of the lead lined wall.
And most important is to check the thickness of the lead lining. Typical is 1/16″ thick, but I have seen 1/8″ thick.
Hi Lori. I think the source was the National Council on Radiation Protection & Measurement Report No. 147 – Structural Shielding Design for Medical X-Ray Imaging Facilities (2004). It’s an 80 USD pdf, but the authors of the report published a detailed presentation of their methods at https://www.aapm.org/meetings/07ss/documents/simpkinradiationshielding.pdf
The method explanation shows alternate shielding materials on slide 105. Steel need to be as 8 times the thickness for lead, so a half-inch or longer steel bolt will provide the same protection as 1/16 inch of lead (see slide 127 for where to use 1/16 inch.)
One thing of interest to me was when at a job site, I noticed that the lead shield drywall did not go full height up the wall.
Per Lloyd’d power point link, the steel needs to be 8 times the lead thickness in order to provide the same protection. If we have a door that is 1-3/4″ thick with lead under both faces (vs. center lead), the mortise lock pocket is protected everywhere except where the holes are drilled through the door for mounting screws, cylinders, spindles, etc. The screws filling the mounting holes will be at least 1-3/4″ long. The cylinder will be at least 1″ long and the spindle is at least half the thickness of the door. Therefore, every penetration is filled with a bolt, spindle or cylinder that should offer far more protection than the lead.
Why use a lead-lined lockset?
Why use lead-lined closer covers?
Same with kickplates. If the screws penetrate the lead on one side of the door, the other side is still solid so, between the screw and half the lead, the door remains protected.
I don’t think lead-lined hardware is necessary for most typical applications but here are always exceptions.