Load Rating Recommendations

Load Rating Class A

Load Rating Class A

• Loads of 1-60 psi.

• Recommended for pedestrians, bicycles and wheelchair traffic.

NDS Load Rating Class B

Load Rating Class B

  • Loads of 61 - 175 psi
  • Recommended for medium-duty pneumatic tire traffic, autos and light trucks at speeds less than 20 m.p.h.
NDS Load Rating Class C

Load Rating Class C

  • Loads of 176 - 325 psi
  • Recommended for heavy-duty pneumatic tire forklifts and tractor trailers at speeds less than 20 m.p.h., H-20 rated
NDS Load Rating Class D

Load Rating Class D

  • Loads of 326 - 575 psi
  • Recommended for heavy-duty hard tire forklifts at speeds less than 20 m.p.h., H-20 rated

Notes: Some installations may require a concrete collar to meet load rating. Load ratings are based on encasing product in concrete. Product must be installed using NDS instructions.

 

Cast iron grates will oxidize over time and rust, forming an iron-oxide patina. The iron-oxide layer begins red-orange in color and ages to a deep, rich brown. This patina is tightly adhered and protects the iron beneath it from further oxidation. Iron grates with a rust patina are structurally sound and will last for decades.