American Association of State Highway and Transportation Officials (AASHTO) M306-04 Standard Specification for Drainage, Sewer, Utility, and Related Castings test specifications are used to predict how manhole covers, grates, and castings will perform. H20 and H25 highway load ratings are applied to the cover and frame for 1 minute. Products that show no visible cracks and deflection of less than 1/8 inch pass the test.

The products are:

  •  FL760 standard-duty (30-inch-diameter) manhole cover passed the H20 40,000-pound load standard
  • FL90 heavy-duty (36-inch-diameter) manhole cover passed the  H25 50,000 pound load rating standard

Since introducing composite covers to the gas station market in the early 1980s, Fibrelite  has applied the technology to steam covers (third-party tested for temperatures up to 400° F) and trench panels.

The anti-slip, anti-static covers mate with a molded fiberglass enclosure to keep underground systems watertight.

For more about manhole covers and risers, read: