Education about the practices for each company is crucial. Your employees should be trained, upon being hired, about what does and does not go into your containers. Making sure they are not putting something into your RMW containers that can go into Solid Waste can help out a lot.
Segregation may seem like a pain at times, but it can help in the long run. Keeping your RMW containers away from any Solid Waste containers can decrease the urge to throw Solid Waste into your RMW containers, decreasing the amount you generate and the cost you incur.
Keeping your RMW containers in your exam rooms close to where you do procedures may seem convenient, however it also allows the general public that comes to your establishment access. They are more likely to throw something away that doesn't belong in your RMW container if it is near by.