In a historic milestone for health in the western region of Guatemala, Dr. Mariza Chan inaugurated the first radiotherapy center equipped with a linear accelerator. This technological advance represents a new era in cancer treatment for thousands of Guatemalans.
Room Dimensions Requirements to Install a Linear Accelerator
What are the vault room dimension requirements to install a linear accelerator?
This is a question we often field at ROS. It’s also not that easy to find the answer for various manufacturers in one place. We recommend referring to the manufacturer’s installation manuals (in the case of Varian, the Designers’ Desk Reference or DDR for short) for the exact model of the linac that you are installing, as precise dimensions for minimum room sizes and other parameters may vary slightly. Nonetheless, these are general numbers that can be helpful when planning on building out your new vault.
General Room Dimensions for Linear Accelerators
| Linear Accelerator | Optimal Room Height | Optimal Room Width | Optimal Room Length | Base Frame Pit Dimensions (LxWxH)(ft.) |
| VARIAN | ||||
| TrueBeam | 9′ | 20′ | 20’6″ | 12’4″ x 5’6″ x 1′ |
| 21/23 Series | 9′ | 20′ | 25′ | 13’9″ x 5’6″ x 1′ |
| 6MV Series | 9’6″ | 20′ | 22′ | 10’3″ x 5’6″ x 1′ |
| Silhouette Series | 9′ | 20′ | 22′ | 12’3″ x 5’6″ x 1′ or 21/23 Series VEO |
| ELEKTA | ||||
| Synergy | 10’6″ | 19’8″ | 20’9″ | 4’8″ x 5′ x 10″ |
| Precise | 10’6″ | 19’9″ | 20’9″ | 4’8″ x 5′ x 10″ |
| Versa HD | 10’6″ | 21’9″ | 20’2″ | 4’8″ x 5′ x 10″ |
| SIEMENS | ||||
| Oncor | 9’6″ | 20′ | 20’6″ | 11’2″ x 5’3″ x 1’2″ |
The more common makes/models of linear accelerators installed today are the Varian TrueBeam and the Elekta Versa HD. However, many older models are still being installed in the secondary equipment market as well.
Varian TrueBeam Room Dimensions
There are two types of Varian TrueBeams, which require different vault room dimensions. They are referred to as “Long Stands” and “Slim Stands” (or SVC for small vault configuration). As a general rule, TrueBeams with a serial number below 2000 are considered Long Stands and those with a serial number 2000 or higher are Slim Stands.
Minimum Pit Dimensions – 5’6” wide x 12’4” long minimum (2’9” + 9’7”) (1’0″ deep)
Minimum Ceiling Height Minimum – 9’0” (finished floor to finished ceiling) although a higher ceiling is recommended to make the rigging easier. Also, anything hanging below the ceiling height (smoke detectors and sprinklers) can interfere during the rig and during operation.
Slim Stand Minimum Room Clearance Required (wall to wall) – 19’4” x 19’4”
Long Stand Minimum Room Clearance Required (wall to wall) – 20’6” x 20’0” wide. This is not really specified in the DDR so it is calculated by taking the couch radius and adding it to the Iso-Center distance from the back wall.
Elekta Versa HD Room Dimensions
Minimum Ceiling Height Minimum – 10’6” (finished floor to finished ceiling) although a higher ceiling is recommended to make the rigging easier. Also, anything hanging below the ceiling height (smoke detectors and sprinklers) can interfere during the rig and during operation.
Minimum Room Clearance Required (wall to wall) – 21’9” x 20’2” wide.
Minimum Pit Dimensions – 4’8″ wide x 5’1″ long (10″ deep)
Conclusion
There is not a one-size-fits-all blueprint for installing a linear accelerator. While we provided the typical room dimensions, schematics may vary due to multiple factors. The actual minimum room dimensions can be smaller, and if you want to limit the full rotation of the treatment couch, you can install in even smaller spaces. For further information, contact ROS and see how we can help with your linear accelerator mechanical and electrical installation, base frame installation, and room preparations.
Related Posts
Can the bunker for LINAC machine be built on the 4th floor of an existing building?
Thanks
It is possible, but likely very difficult and expensive. Bunkers require shielding on every wall, and depending on location, on ceilings and floors. Shielding is expensive, heavy, and occupies space that eats into the available bunker room.
I am designing a hospital that will have the Varian TrueBeam Linear Accelerator, what is the weight and dimension of the linear accelerator so that I can design the correct foundation for the building?
Thank you for your comment, Nkateko. The best way to ensure that you are planning properly is to make sure you have a copy of the Varian Designer Desk Reference (DDR) or Installation Data Package (IDP) from Varian that is specific to your TrueBeam model and year of manufacture.
Mechanically working on a True Beam installation in several months . . Do you have any required cooling loads available that you know of or a HVAC ductwork layout. Ductwork installation guide ? 3 ton load ? – 4 ton cooling load ?, ect.
Thank you..
Hi Terry. The answers to most of those questions will be in the Varian TrueBeam Planning Documents. Were you provided a set of those documents given you were tasked to prep a portion of the vault for a TrueBeam? I will email you directly to see if ROS can help.
Hi, we are designing a hospital that will have the Varian TrueBeam Linear Accelerator. Can there be any patients rooms just above the vault of the linear accelerator? What is the requirements around the linear accelerator? Thank you.
Hi MR. Buyantamir,
This is possible, provided there is adequate shielding added to the ceiling of the treatment room. One should consult with a medical physicist to develop vault shielding calculations to determine the amount of shielding that would be required.
Best regards,
The ROS Team.