Threshold and hounsfield unit inclusion

Operating system: Windows 10
Slicer version: 4.1.1.

I am using threshold method to measure ROI. A question came up if the threshold is set at -30, is -30 included or does the inclusion of values start from -29?

The threshold range is inclusive on both sides.

Note that 1 HU is such a small difference that it should not matter either way. For example, magnitude of image noise typically tens of HU.

Thank you for the information. Knowing the noise level is very helpful.