@bens1 According to literature, Elekta machines have auto shut off. There is the Elekta MR-Linac (there are very few of them in Ontario-& Quebec-Canada, compared to the older generation Elektas) but I was told that it's used only for patient's with high risks of healthy organ damage (e.g., prostate cancer patients who cannot have the gold seeds fiducial markers implanted). I have gold seeds.