attached to an electric fan 200 in this embodiment rotating fan guard 100 is connected to fan 200 by attaching center disk 115 of fan guard 100 to hub 220 of the fan rotor 215 on the intake side of the fan 200 fan guard 100 rotates in synchronism with rotor 215 and fan blades 205 air flow through the fan 200 is in direction 310 the concentric guard rings 105 of fan guard 100 are spaced closely enough to prevent the fingers of maintenance personnel from passing between the guard rings 105 and contacting the rotating fan blades 205 fig1 shows an underwriter 39 s laboratories iec 529 34 test finger 34 1500 hereinafter referred to as a 34 ul finger 34 1500 in fig1 a 60 millimeters mm b 30 mm c 20 mm and d 10 mm the diameter of ul finger 1500 at cross section e e is 12 mm fig1 is cross section taken through line 16 16 of fig1 fig1 is a cross section taken through line 17 17 of fig1 in order to comply with ul requirements the spacing s between rings 105 must be such that a 34 ul finger 34 1500 cannot pass between the rings 105 therefore the spacing s in one embodiment of the present invention is approximately 0 3 inches or less the fan guard 100 is typically used with an electric fan 200 such as an ebm industries type w2g 107 this fan 200 has a blade diameter of approximately 4 15.