Structural grating has traditionally been made of steel, but composite grating is an alternative. This fibergrating is an advantage in applications where the lower weight and non-corrosive properties are ideal.
Common applications for grating are elevated platforms and walkways. The decking for these structures need to support human loads at a minimum, and additional loads depending upon application. One safety concern would be that of impact loads. Heavy loads falling onto the grating have a high potential to cause damage.
There are lots of people that believe in steel as being the strong alternative. Fiberglass can be superior as shown in this clip from The Composites Channel
As you can see, a drop test is performed in similar fashion on both steel and fibergrating. The fibergrating is superior to steel grating for this test.