The Sinner's Circle: The basics of cleaning

Why do you wash dishes with hot water and why should you leave some dirt to soak? When cleaning, everything evolves around the four basic factors of time, mechanical, chemistry and temperature – if you understand the connection between these, even the most stubborn of cleaning issues are easy to tackle.

The cleaning circle

The cleaning circle, named after Dr Sinner and otherwise known as the "Sinner's Circle", describes the effect mechanism when cleaning. It contains four basic factors that play an important role when cleaning: Time, mechanical force, chemistry and temperature. The circle always remains closed: If one or two of the four factors are increased, the other factors are automatically decreased. If one factor is reduced, other factors need to be increased. The principle can be clearly demonstrated using the example of dish-washing.

The four basic factors of cleaning

Time

The time factor describes both the contact time and the working time. Thanks to a longer contact time, stubborn dirt is softened and is then easier to loosen. A typical application case is a pot with burnt-on food residues. If the pot is left to soak for an extended period of time, the dirt is considerably easier to remove. This not only reduces the working time, it also means that fewer mechanical actions and less detergent are required.

Temperature

Anybody who has ever tried to do the washing-up with cold water recognises the phenomenon: Oily, greasy and waxy dirt is easier to loosen when warm or hot water is used. However, other dirt can also be loosened more effectively and more quickly when high temperatures are used. The contact time and the working time are reduced, and washing the dishes by hand is a significantly quicker task. This reduces the need for the mechanical and chemical.

Mechanical

With "Mechanical", we mean the force that is required to loosen dirt. It consists of various factors: The abrasiveness (scrubbing effect), the contact pressure and the frequency of the movement. A steel sponge has a high level of abrasiveness but would easily scratch soft surfaces. In contrast, if you use a soft cloth, you require more contact pressure and you have to wipe over the dirty area multiple times in order to completely clean it.

Chemicals

Choosing the right detergent plays a key role in many cleaning tasks. Dirt can often only be removed by using a detergent since the other three factors cannot be increased indefinitely. Where dirt is burnt on to a baking tray, for example, a long contact time and laborious scrubbing are no longer of any use; it is only when a suitable detergent or household remedy is used that the tray can be restored to its former glory. Chemicals can also be used to remove water-insoluble dirt. The surface tension of the water is reduced, meaning that the entire surface can be wetted and the cleaning solution can penetrate even the smallest of cracks and pores.

The Sinner's Circle in practice

The Sinner's Circle is part of the core knowledge of every professional building-cleaner and the described mode of action is regularly used in commercial cleaning. However, the basic principle of the cleaning circle can also be applied to many everyday cleaning tasks and is therefore useful for your own household.

A woman setting the washing machine to the eco programme

Eco washing programme

Modern washing machines have so-called eco programmes, in which the duration of the washing cycle is increased and, at the same time, the temperature is reduced. The same cleaning results can therefore be achieved but with lower energy use; the circle remains closed here.

Steam cleaner

Steam cleaners primarily achieve their cleaning power with hot steam. They usually require very little mechanical support in order to loosen dirt, and chemical detergents can also usually be completely avoided.

Pressure washer

A pressure washer creates a strong mechanical effect and, in many cases, achieves excellent cleaning results, even without the other factors. The working speed regulates the "Time" factor – with light dirt, you can work faster. However, the cleaning power can also be increased with special detergents.