This standard specifies the general requirements, grading, materials, manufacture, and load testing for cast iron manhole covers and frames used in drainage and sewerage networks. It categorizes covers into four grades (LD, MD, HD, EHD) based on their load-carrying capacity to suit various traffic conditions.
Details specific requirements, including load ratings and dimensions, for different classes of cast iron manhole covers and frames.
Quick Reference Values
light duty LD test load2.5 tonnes (25 kN)
medium duty MD test load10 tonnes (100 kN)
heavy duty HD test load20 tonnes (200 kN)
extra heavy duty EHD test load35 tonnes (350 kN)
minimum material gradeFG 150 of IS 210
dimensional tolerance± 5 percent
Practical Notes
Always match the cover grade (LD, MD, HD, EHD) strictly to the expected traffic load of the installation site to prevent structural failure.
Ensure the seating of the cover in the frame is checked prior to installation to prevent rocking and noise under traffic.
Covers and frames must be coated with a bituminous or suitable anti-corrosive paint immediately after casting to prevent rusting.