Patterns A & B
A & B patterns conform to the AS 1657 Code for Fixed Platforms, Walkways, Stairway and Ladders.
These patterns are the most commonly specified and installed. This type of grating with its 30mm load bar centres has the greatest resistance to surface impact. It is used extensively in Power Stations, Refineries, Sewerage Treatment Plants, Grain Silos, Chemical Plants and for trafficable drain grates and stair treads. In serrated form, patterns A & B are used in wet, greasy areas especially in the oil industry on offshore production platforms.
NB: Serrations are not as effective in the B pattern because of the pitch of the cross rods.