<prompt> High brachytherapy is0.4-2 Gyhour12 Gyhour2-12 Gyhour0.01-0.3 Gyhour  <response>: According to ICRU repo 38, treatment dose rates fall into three categories Low Dose Rate LDR brachytherapy ranges between 0.4 and 2 Gyh. However, in routine clinical practice, LDR brachytherapy is usually delivered at dose rates between 0.3 and 1 Gyh. This is compatible with conventional manual or automatic afterloading techniques. Medium Dose Rate MDR brachytherapy ranges between 2 Gyh and 12 Gyh. MDR can also be delivered by manual or automatic afterloading, although the latter is far more frequent. High Dose Rate HDR brachytherapy delivers the dose at 12 Gyh or more, and only automatic afterloading can be used because of the high source activity.Ref: Radiobiology of Brachytherapy and the Dose-Rate Effect by JJ Mazeron et al, 95 