The most important thing to do is vacuum and dust mop regularly and as often as necessary. For some families and most businesses, this may mean every day. Don’t damp mop on a weekly schedule as this will cause the finish to wear faster . Damp mop only as needed when the floor is dirty. Even then, cleaning on a spot basis will suffice. When you do need to clean the floor, we recommend water and vinegar and a lightly damp mop. You should not use anything that leaves a residue. Even the products that spray on a mop have silicones that can interfere with the finish and oil soaps can cause intercoat adhesion problems.
First, there is no standard for determining if a crack of a particular size is not acceptable or excessive. Cracks are considered “normal cracks” if they close during the humid season of the year. If the cracks close, the natural wood product is simply absorbing the environmental moisture available, expanding and filling the gap.
To prevent unsightly normal cracks, the environment must be modified to minimize the difference between “Humid” and “Dry” seasons. De-humidification above and below the flooring in the summer may be necessary; conversely, humidification during winter heating may also be required.
Permanent cracks may be filled with an appropriate filler and/or recoating the flooring. This should generally be done during the Spring or Fall when conditions are not extreme and more average. For much of the USA, October and April are the preferred months for remedial action.