Q.: Within a short time after we completed a 40,000-square-foot warehouse floor we were called in and asked how to remove oil stains that had already been spread all over the floor by lift trucks. We are studying the methods described in the article in the September 1986 issue (page 821), but we're wondering what to advise future owners for whom we build floors about how to prevent oil stains. We've heard there are diapers for lift trucks.
A.: Yes, on special order some manufacturers of lift trucks will make oil-catching metal pans, popularly known as diapers, which can be connected to the frame. There is no standard design and they aren't stock items. Diapers can also be made by local sheet metal fabricators. Unfortunately, use of a diaper restricts air flow under an air-cooled engine and is bad for engine performance. This should be less of a problem for electric-powered trucks. Some operators use a piece of rug in the pan to absorb oil, but this seems to be bad practice because it is likely to be a fire hazard.
One manufacturer who makes both internal combustion engine trucks and electric trucks reports that lift trucks are notorious for oil drippage because they have so many potential sources for leaks. However, drippage from electric trucks is about half as much as from others. The same truck manufacturer thinks the best solution is to coat the floors with an epoxy or polyurethane coating, from which the oil can be easily cleaned. This solution can have the disadvantage of making the floor slippery enough to cause the truck wheels to spin sometimes. For that problem the application of a dust-on slip-resistant aggregate to the freshly applied coating may be helpful. The manufacturer of the coating should be able to provide full details and instructions.