Cleaning chemistry – pH, dirt types and correct dosage
Understand what the agent does and choose the right one for the task
A cleaning agent is not just 'soap'. It is chemistry composed to loosen a particular kind of dirt. Choose wrong and you work against the chemistry: a basic agent does not bite on lime and an acid agent does not remove grease effectively. Understand what the agent does and you stop guessing and start choosing right.
§pH scale — acidic, neutral, alkaline
pH is a measure of how acidic or alkaline a substance is. The scale runs from very acidic at one end, through neutral in the middle (pure water), to very alkaline (basic) at the other end. The rule of thumb in cleaning is simple: acidic agents dissolve limescale and rust, alkaline agents dissolve fat and protein, and neutral agents are gentle for daily cleaning of sensitive surfaces. Match the type of dirt with the pH of the agent.
| pH range | Usually used for | Example of dirt. |
|---|---|---|
| Sour | Descaling and rust removal | Limescale in bathrooms and on taps, urinary stone |
| Neutral | Daily gentle cleaning | Light, mixed dirt on sensitive surfaces |
| Basic (alkaline) | Fat and protein dissolution | Fat in kitchen, soot, ingrained grime |
§The building blocks of the product
A cleaning agent consists of several components each with a task. The most important group is surfactants that reduce the surface tension of water so it can penetrate and loosen dirt and hold it suspended until it is rinsed away. Also often included are builders that bind lime in the water and possibly solvents enzymes and fragrances and preservatives.
- 01Surfactants: reduce surface tension, loosen and wrap dirt
- 02Building materials/lime binders: bind hardness in water so detergents work better
- 03Solvents: help dissolve grease and oil
- 04Enzymes: break down specific soil such as protein, fat or starch
- 05Fragrance and preservatives: additives without cleaning effect.
§Sinner's circle — four factors working together
The cleaning effect doesn't come from chemistry alone. Sinner's circle describes four factors that together give the result: chemistry, mechanics (friction), temperature and time (working time). They form a whole – if you turn down one, you have to turn up another. Less chemistry can be compensated by more mechanics or longer working time; colder water can require more agent or time. That's the explanation for why microfibre and good friction can clean with very little agent.
§Dosage and contact time
Always dose according to the manufacturer's instructions on the label, and use dosing aids rather than eyeballing. Overdosing does not give cleaner surfaces — it leaves soap residue that binds new dirt and can make surfaces sticky or dull, and it unnecessarily burdens wastewater. Many products also need contact time: they must stand and work before being wiped off. Rinsing too quickly is a common mistake that costs effectiveness.
§Safety when mixing chemistry with the task
Never mix different products together. Certain combinations — such as a chlorine-based and an acidic product — can develop toxic gases. Use one product at a time, and rinse between if you switch. Read the hazard and precautionary statements on the label and the associated safety data sheet before using a new product, and use the protective equipment indicated. Both acidic and basic chemistry can be caustic to skin and eyes.
“Cleaning chemistry works when it's allowed to: the right agent, the right dosage, the right working time – and a bit of mechanics on top.”
— Professional basic rule.