They're using a commercial scanner: https://www.sizestream.com/technology https://www.sizestream.com/technology The margin of error is less surprising if you c

They're using a commercial scanner: https://www.sizestream.com/technology https://www.sizestream.com/technology The margin of error is less surprising if you consider that they're interested in the precision of measurements like hinged upper bust circumference, not the position of raw points in a point cloud. According to the paper "Erroneous measurements occur because of the 3 D Body Scanner’s incorrect placement of anthropometric landmarks or the physical positioning of body parts which increase measurement paths against the algorithms. The 3 D Body Scanner’s incorrect landmark and measurement placement, in this study, causes measurements with a range of up to 32.9 cm (M=14.6 cm; SD=12.67 cm)." I.e. if the scanner confuses your arm for your leg, that's going to throw off the measurements a lot. It seems like SizeStream could easily improve their product by applying some basic filtering to remove outliers.