Strange ID when save a file as SVG in Illustrator

I drew a map of a floor with offices in Illustrator, and I need to named each office floor. But the names have numbers or special characers such () and +, i.e. 360 (IVO+IMR+IEC) And when I save it as a SVG file, the id are id="_x33_60__x28_IVO_x2B_IMR_x2B_IEC_x29_" Why happen this? How can I fix it or avoid?