"Is there any way to tell if an improper lubricant is being used without performing an oil analysis or without a part or system failure? We currently have an oil analysis program in place, but I still find that wrong oils and fluids are being used from time to time in between the oil analysis."
The most effective way to determine if wrong oil has been used is by oil analysis, by looking at either a change in viscosity and/or a change in additive concentration, etc. Unless there is a significant difference in oil type (viscosity, base oil type, additives, etc.) or any dye that may be used in the oil or grease, it is unlikely that a sensory inspection is sufficient.
However, your problem probably has little to do with oil analysis but is more of a procedural issue. The bottom line is that you need to make those who are empowered with adding/changing oil understand why adding the wrong oil is bad.
The first stage is understanding through education, whether it be formal training or simply internal training sessions. Secondly, you need to make the process of adding oil as foolproof as possible. The best way to achieve this is to practice lube tagging. In this approach, new oils are tagged with a designated color and shape. For example, ISO VG 220 gear oil is given a red circle, AW 46 hydraulic fluid a green square, etc.
The next step is to similarly label dedicated oil transfer equipment such as oil top-off containers, funnels, filter carts, etc.
Finally, label the gearboxes, etc., with the same red circle, green square, etc. The strategy is simple: Red-circle oil gets added to red-circle components using red-circle hardware. This can be applied to all components and hardware, including greases, grease guns, etc.
A good example of lube tagging occurred at the General Motors Linden Assembly Plant in New Jersey. Management addressed the need to coordinate the equipment requirements with the labeling of lubricant storage and delivery containers. It created a coding system that used words, images and colors to define the specific product for each application. Once identified, the products were then matched with the correct storage and transfer container.
The result was a visual system that clearly communicated which lubricant the machine required and which container held that particular lubricant. The technician or mechanic needed no special knowledge to use the simple matching system.