ECJ EUROPEAN Cleaning Journal

Dutch correspondent Anton Duisterwinkel summarises a new study on floor cleaning by research organisation VSR.

There is much dispute and uncertainty on the best way to use microfibre mops. These flat mops are an effective, efficient and ergonomic means for cleaning lightly stained hard floors, after removing the dust by a Swiffer-like method. In fact, the flat mops look quite similar to the Swiffer. One big difference is that the microfibre flat mop is typically used wet, rather than dry.

It is unclear, however, how much water will give the best results. Some suppliers state that very little water should be used, down to 80 per cent of the mop weight. In other words: for a mop weighing 100 grams, only 80 grams of water should be added. Other suppliers advice the use of 320 per cent of water by weight, that is more than three times the weight of the mop.

VSR, the Dutch Association for Cleaning Research, wanted to clarify this situation and commissioned SOHIT, an independent lab that is connected to Wageningen University, to investigate the effect of water content on cleaning; on dirt entrapment; and on ergonomy. That is: the force needed to move the wet mop over the floor surface.

Indeed, the water content of the microfibre mop does play an important role in cleaning. When the mop is too dry, cleaning is slow and incomplete. This rapidly improves by adding more water. However, when the mop becomes too wet, it will leave a water residue on the floor. Not only does this make the floor slippery and sensitive to resoiling, but the water left behind is in fact dirty and will leave stains upon drying. When moving a very wet mop from a dirty floor to a clean floor, in fact a smearing effect can be seen for very wet mops.

In short, an optimal wetness value exists for each mop. And the surprising bit is that the optimal wetness value is for almost all cases between 160 and 200 per cent, although rather different microfibre mops were tested. Also, the type of flooring and the type of dirt had limited influence. The optimal wetness values were very pronounced for water soluble stains, but was also observed for a fatty stain mimicking human skin fat.

Moving mop

Also remarkable is that the force needed for moving the wet mop over the floor was independent of the water content of the mop, at least in the range of wetness values that was investigated. Thus, any value of wetness is OK with regard to ease of use.

In practice it appears best to wet the microfibre mops with about twice the weight of water as compared to mop weight, although a small optimisation may be needed for certain floor types, for instance very porous floors.  In use, the mop will lose some of the water and therefore become a little drier and therefore even more effective.

This research is a good example of what VSR wants to achieve: more professional cleaning based on facts and knowledge, rather than guesses and unconfirmed theories. Research continues!