Load Class Definitions
Grate Load Class Definitions
ANSI A112.21.1M
Grates shall be designed to meet the following loading classifications in a static condition.
DIN 19580
Grates shall be designed to meet the following loading classifications in a static condition.
Transportation Classifications
- According to the American Association of State Highway and Transportation Officials (AASHTO) “Standard Specification for Highway Bridges,” H-20 loading refers to a two-axle truck with a maximum dual-wheel load of 16,000 lbs, while HS-20 loading describes a tractor truck with a tandem axle semi-trailer, also with a dual-wheel load of 16,000 lbs.
- The FAA (Federal Aviation Administration) Advisory Circular AC 150/5320-6D specifies aircraft loading as 100,000 lbs distributed over a 9” x 9” area.
- The Americans with Disabilities Act (ADA) requires that slot widths on gratings in walkways be no more than 1/2 inch, with elongated slots positioned longitudinally, perpendicular to the primary direction of travel.
- Heel Proof refers to slots or perforations that are less than 1/4 inch in width or diameter.
- The maximum safe live load is determined by dividing the failure load by two.
