Linac head position

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Soapcat

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I am reviewing a blueprint of a radiation clinic, and would love hear your thoughts.
In this version, I noticed the treatment room is parallel to the offices. There is a primary barrier at the angle of radiation delivery angle (see below) but still there are rooms right next to it.

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Most of radiation clinics I have seen/worked at placed the linac at the corners of the building, where the head does not directly face towards the offices. Assume an average busy clinic utilizing 6-10 MVs w/ a decent number of IMRTs/SBRTs.

Is enough of primary barrier (e.g. concrete) and some distance enough to mitigate the exposures? In other words, do you feel comfortable with a design that allows an exposure that is within what radiation workers are allowed to receive per year? The offices are where a staff (e.g. MD) will be sitting all day while the beam's on.
 
My office is directly next to a vault, but there isn't even a hallway in between.

Dosimeter measurements have been perfectly fine.
 
An important consideration in shielding is usage factor. In other words, how frequently and how often will people be on the other side of the vault wall? For parking lots, sidewalks, and similar public areas, the usage factor is low. For an office, that means increased shielding. You should ask for the assumptions they assume in the usage factor (hopefully ~40 hours of human occupancy each week).

In CA, even after the vault goes online, there is post-construction dosimetry that occurs for several months to assure that calculations were correct.
 
An important consideration in shielding is usage factor. In other words, how frequently and how often will people be on the other side of the vault wall? For parking lots, sidewalks, and similar public areas, the usage factor is low. For an office, that means increased shielding. You should ask for the assumptions they assume in the usage factor (hopefully ~40 hours of human occupancy each week).

In CA, even after the vault goes online, there is post-construction dosimetry that occurs for several months to assure that calculations were correct.
Also IMRT and SBRT frequency (which translates to more MUs per treatment, on average) in a practice contribute to that usage factor.
 
I am reviewing a blueprint of a radiation clinic, and would love hear your thoughts.
In this version, I noticed the treatment room is parallel to the offices. There is a primary barrier at the angle of radiation delivery angle (see below) but still there are rooms right next to it.

View attachment 407513
Most of radiation clinics I have seen/worked at placed the linac at the corners of the building, where the head does not directly face towards the offices. Assume an average busy clinic utilizing 6-10 MVs w/ a decent number of IMRTs/SBRTs.

Is enough of primary barrier (e.g. concrete) and some distance enough to mitigate the exposures? In other words, do you feel comfortable with a design that allows an exposure that is within what radiation workers are allowed to receive per year? The offices are where a staff (e.g. MD) will be sitting all day while the beam's on.

I mean, if you're worried about the MDs in the office beyond the hallway, what about the poor therapists in the console room? They're cooked if you're worried about the physicians.

*EDIT* - Does 'room' mean console room? Or exam room? If exam room, then where is the console room?
 
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