Reflected ceiling plans denote the view of a floor, space, or room as it would be seen from the ceiling. Hence, all the suspended items from the ceiling are presented in these layout plans. These ceiling plans vary based on the type of floor or space, and so do the associated elements and symbols. A ceiling plan layout may include symbols of grille diffuser, rectangular ducts, linear return diffuser, rectangular inlets, etc. These symbols depend upon the shape of the element as seen from above and are named accordingly. Also, as these elements can be present as more than one in number, they are numbered accordingly.