indicator device 10 shown in fig1 a includes a circular base element 11 with a front surface 21 back surface 22 an outer edge 23 and inner edge 24 which forms a center aperture 25 the embodiment of fig1 a further includes an attachment element 70 and light emission element 80 the attachment element 70 is adhesive tape 71 on the back surface 22 of the base element 11 and the light emission element 80 is strontium silicate material 81 on the front surface 21 of the base element 11 it is contemplated that the strontium silicate material 81 may further include magnesium other embodiments according to the present invention include a safety marker indicator device 10 with a four sided base element shown in fig1 b as a square base element 12 and shown in fig1 c as a rectangular base element 13 as shown in fig1 b and fig1 c the four sided base element 12 13 includes a front surface 31 back surface 32 an outer edge 33 and inner edge 34 the inner edge 34 comprises a first border 41 second border 42 third border 43 and fourth border 44 that forms a center aperture 35 the outer edge 33 comprises a first boundary 45 second boundary 46 third boundary 47 and fourth boundary 48 as shown in fig1 b attachment element 70 is a liquid adhesive 72 on the back surface 32 and the light emission element 80 is a zinc sulfide material 82 on the front surface 31 as shown in fig1 c attachment element 70 is velcro u00ae 73 on.