Professor David W. Kammel who is part of the Biological Systems Engineering Department at the University of Wisconsin Cooperative Extension, goes into great detail on safe design of secondary containment facilities, from volume allowance in storage tanks to required wall height of containment areas. Secondary containment refers to structures built around tanks that hold pesticides, fertilizer, rinsate and sludge. Secondary containment, such as a containment curb, is used to trap escaped liquids and or debris that have leaked from the tanks due to simple leaks, fire, vandalism, rupture and spills. Secondary containment systems are designed to provide adequate time for site operators to clean up and capture spills, as well as repair damage to storage containers. Secondary containment is intended to be a safety net, proper design, maintenance and function is essential.
When it comes to the secondary containment floor area, it is necessary to make room for present/future tanks and mixing and transferring equipment. Workers also need space to move around the area without risk of injury. There should be at least 2 feet between tanks, and 2 feet between tanks and the containment walls. To calculate the containment floor area for vertical tanks only and for non-vertical or elevated tanks there are equations provided.
Secondary containment of small storage tank volumes can be incorporated by constructing a small curb. Containment curbs are also utilized for mixing and loading pads for pesticide warehouse or storage rooms. Using containment curbs is also an excellent method for containing bottles, jugs, and small minibulk storage tanks. The curb must be high enough to have sufficient volume to contain any spillage. To provide secondary containment for bulk pesticides or pesticide rinsate, the curb must be at least 4 inches high. Containment curbs make it easier for workers to move around without climbing ladders or climbing over walls.
For operator safety containment curb covers are often constructed out of slip resistant material to allow operators to step on the curb without slipping when wet. SlipNOT® manufactures slip resistant containment curb covers in steel, stainless steel, aluminum and galvanized steel. Each cover is made to the customer’s specific dimensions and can be easily bolted on top of the existing concrete or welded seamlessly to floor plates.