It’s good practice to use ADA grates as pedestrians may walk in and out over the entranceways. We recommend using 12” wide cast iron grates with at least a 1 ½” thickness. These grates are usually used with cast iron or steel frames and set on top of a pre-cast concrete channel.
Gas stations, Driveways and Refueling Stations generally all use the 12” wide standard. Anything smaller, may not adequately drain heavy rainfall and anything larger is usually not necessary. 14” grates are also widely used since they are a commonly stocked item.