Introduction to Industrial Cleaning
Industrial cleaning differs from household cleaning in essentially every respect — in scale, in the required process speed, in the toughness of the soils, and in the strictness of the result requirements. While a household cleaning agent needs to clean a surface so that it looks and smells clean, an industrial cleaning process often has to meet a measurable, auditable criterion: microbiological safety of the surface, absence of residue from the previous batch, or readiness of a metal part for painting or welding.
The market for industrial cleaning and disinfection agents in the EU includes several distinct segments with very different requirements:
Food & Beverage Industry
The strictest requirements — CIP systems, low-foam surfactants, disinfection with proven efficacy (EN 1276), absence of odor and taste in the product.
Metalworking & Mechanical Engineering
Degreasing before surface treatment, welding, or painting. Emphasis on removing cutting fluids, protective oils, and metal wear particles.
Facility Management
Cleaning of large administrative, commercial, and industrial areas. Emphasis on efficiency, low water consumption, and staff safety.
Healthcare & Pharma
High demands on disinfection and sanitation — validated procedures, virucidal and sporicidal efficacy, GMP-compliant documentation.
Automotive & Heavy Industry
Degreasing large metal parts, cleaning paint shops, removing waxes and preservation agents before the next production operation.
A key difference from consumer cleaning is also that the industrial process must be repeatable and validatable. Buyers and technologists must be able to justify why a particular agent was chosen, what its concentration and contact time are, and how efficacy is verified. This guide gives you a practical framework for decision-making — from soil classification through chemistry selection to legislative requirements.
Why chemistry matters more than it seems
A poorly chosen cleaning agent not only fails to clean — it can damage equipment (aluminum corrosion from strong alkali), extend line downtime (insufficient degreasing before disinfection reduces its efficacy), or lead to a complaint due to product contamination with chemical residue.
Types of Soil and How to Classify Them
The basic rule of effective cleaning is: the chemistry must match the type of soil. An incorrectly chosen agent will either fail to dissolve the soil at all, or merely smear it across the surface. Soils in an industrial environment are divided into three main categories.
Organic Soils
Fats, oils, proteins, carbohydrates, and other substances of biological or petroleum origin. Typically require alkaline chemistry (fat saponification) or enzymes (protein and starch breakdown).
Animal & vegetable fats
food operations, kitchens, slaughterhouses
Mineral oils & lubricants
mechanical engineering, cutting fluids, hydraulics
Protein deposits
dairies, meat industry, breweries
Starches & sugars
bakeries, beverage industry
Inorganic Soils
Limescale, rust, mineral deposits, and metal oxides. Typically require acidic chemistry, since acids dissolve carbonates and metal oxides through reactions that form soluble salts.
Limescale (CaCO₃, MgCO₃)
heat exchangers, boilers, CIP piping
Rust & iron oxides
metalworking, piping systems
Beer stone (oxalates)
brewing, beverage lines
Mineral water deposits
cooling towers, steam boilers
Biofilms
Complex structures of microorganisms encased in an extracellular polymeric matrix (EPS). Biofilm protects bacteria from common disinfectants and requires a combination of mechanical action, alkaline cleaning to disrupt the matrix, and subsequent disinfection.
Bacterial biofilm in piping
stagnant sections of CIP systems, seals
Biofilm in cooling towers
Legionella risk, regular sanitation required
Practical rule for choosing chemistry
Organic soil → alkaline chemistry or enzymes. Inorganic soil (limescale, rust) → acidic chemistry. Mixed soil (typical for CIP) → two-phase process: alkaline cycle followed by acidic cycle. Biofilm → mechanical disruption + alkaline cycle + disinfection with proven biofilm penetration (e.g., peracetic acid).
Alkaline Cleaning Agents
Alkaline cleaning agents are the backbone of industrial cleaning for organic soils. They are based on sodium hydroxide (NaOH) or potassium hydroxide (KOH), often supplemented with silicates, phosphates or their substitutes, sequestrants, and surfactants.
The Saponification Mechanism
The key mechanism by which strong alkalis act on fats is saponification — hydroxide ions cleave the ester bonds of triglycerides (fats), forming glycerol and soaps (salts of fatty acids). The resulting soaps are water-soluble and further help emulsify residual fat. This process requires sufficiently high pH and temperature — the reaction speeds up significantly above 50–60 °C.
In addition to saponification, alkalis also hydrolyze proteins (breaking down peptide bonds) and disperse fine soil particles, which is important when cleaning food processing equipment with protein deposits.
| Type of Alkaline Agent | Typical pH | Application |
|---|---|---|
| Silně alkalický CIP prostředek (NaOH 1–2 %) | 13–14 | Removal of fats and proteins, dairies, breweries |
| Alkalický odmašťovač na kovy | 11–13 | Degreasing before painting, galvanizing, welding |
| Mírně alkalický prostředek na hliník | 9–11 | Cleaning aluminum parts, sensitive metals with corrosion inhibitor |
| Alkalický čistič kuchyňských povrchů | 11–13 | Grills, ovens, degreasing baths in food service |
| Pěnivý alkalický čistič (foam cleaning) | 12–13 | Vertical surfaces, production hall walls, conveyors |
Beware of aluminum and sensitive metals
Hydroxides react with aluminum to form hydrogen and aluminates — strongly alkaline agents (pH above 12) rapidly attack aluminum, causing blackening and corrosion. For aluminum parts, choose mildly alkaline agents with corrosion inhibitors (silicates, gluconates) or neutral/acidic alternatives.
Acidic Cleaning Agents
Acidic cleaning agents are used primarily to remove inorganic deposits — limescale, rust, and mineral deposits. The mechanism of action is based on the reaction of the acid with carbonates and metal oxides to form soluble salts, which are then flushed away.
| Acid | Typical pH (solution) | Main Use |
|---|---|---|
| Kyselina fosforečná (H₃PO₄) | 1–3 | Limescale removal, conversion coatings, food-grade CIP |
| Kyselina citronová | 2–4 | Gentle descaling, food contact, safe handling |
| Kyselina sulfamová | 1–3 | Descalers for boilers and heat exchangers |
| Kyselina dusičná (HNO₃) | 1–2 | Passivation of stainless steel, strong CIP acid cycles |
| Kyselina chlorovodíková (HCl) | 0–2 | Removal of rust and heavy mineral deposits (limited use due to vapor corrosivity) |
Safety Considerations
Strong mineral acids (phosphoric, nitric, hydrochloric) require appropriate personal protective equipment (safety glasses, acid-resistant gloves and clothing) and must be stored separately from alkalis and oxidizing disinfectants. Hydrochloric acid also releases irritating vapors, so phosphoric or sulfamic acid is preferred in enclosed spaces.
Citric acid as a safe alternative
Citric acid is biodegradable, non-toxic, and safe for food contact, making it popular in the food and beverage industry for descaling cycles, even though it has lower efficacy against heavily built-up limescale than phosphoric acid.
Neutral and Enzymatic Cleaning Agents
Not all surfaces and applications can withstand extreme pH. For sensitive materials (aluminum, galvanized sheet, some plastics, painted surfaces) or for everyday maintenance cleaning, neutral detergents with a pH close to 6–8 are used, based on nonionic and amphoteric surfactants with good wetting and low foaming.
Enzymatic Cleaning Agents
Enzymatic agents use biocatalysts to target the breakdown of specific types of organic soil under mild conditions (lower temperature, neutral to mildly alkaline pH). This saves energy and is gentle on materials sensitive to extreme pH.
Proteázy
Break down proteins into peptides and amino acids. Key for cleaning blood, milk proteins, and food residues.
Lipázy
Hydrolyze fats and oils into fatty acids and glycerol. Complement or replace alkali saponification at lower temperature.
Amylázy
Break down starches and carbohydrates into simpler, water-soluble sugars. Common in the bakery and beverage industry.
Enzymatic agents have their limitations: enzymes are sensitive to extreme pH, high temperature (they usually function optimally in the range of 30–50 °C), and the presence of strong oxidants or disinfectants that deactivate them. They are therefore not suitable as a universal substitute for strong alkaline CIP chemistry where a fast cycle at high temperature is needed.
Low-Foam Formulations
For machine washing, CIP systems, and pump circuits, excessive foam is a problem — it reduces the effectiveness of the mechanical action of the flowing liquid and can cause pump failure. Neutral and enzymatic agents for these applications are therefore formulated with low-foam nonionic surfactants (EO/PO block copolymers) instead of high-foam anionic surfactants such as LAS or SLES.
CIP (Clean-in-Place) Systems
CIP (Clean-in-Place) is a method for cleaning the interior surfaces of pipes, tanks, heat exchangers, and other equipment without the need for disassembly. It is standard in the dairy, brewing, beverage, and pharmaceutical industries, where it enables frequent and reliable cleaning of closed systems.
Phases of a Typical CIP Cycle
1. Pre-rinse
Water (often recycled from the previous cycle) removes coarse product residue. Usually takes 5–10 minutes, at ambient to slightly elevated temperature.
2. Alkaline wash cycle
Circulation of NaOH solution (0.5–2%) at 60–80 °C for 15–30 minutes. Removes fats and proteins through saponification and hydrolysis.
3. Intermediate rinse
Rinsing out alkali residue with water; the conductivity of the outlet water is often monitored to confirm sufficient rinsing.
4. Acidic wash cycle
Circulation of nitric or phosphoric acid (0.5–1%) at 50–70 °C, usually 10–20 minutes. Removes mineral deposits and neutralizes alkali residue.
5. Final rinse and disinfection
A final rinse with potable or process water, possibly followed by a disinfection step (chemical or thermal) before returning the system to operation.
Sinner's Circle — Four Factors of the Cleaning Process
Herbert Sinner formulated a principle in 1959 that still governs the design of every CIP process today: cleaning effect is a function of four mutually interchangeable factors — chemistry (agent concentration), temperature, contact time, and mechanical action (represented in CIP systems by turbulent flow and flow velocity in piping, or nozzle pressure in tank equipment).
If one factor is limited (e.g., temperature cannot be increased due to the risk of protein burn-on on the heating surface of a heat exchanger), it must be compensated for by increasing the others — a higher chemical concentration, a longer cycle time, or a higher flow velocity (typically 1.5–3 m/s in piping for sufficient turbulent flow).
Practical compensation example
If an operation reduces the alkaline cycle temperature from 80 °C to 60 °C to save energy, it is necessary either to extend the circulation time by 30–50%, or to increase the NaOH concentration by 0.3–0.5 percentage points, in order to maintain the same cleaning effect.
Low-Foam Requirements in the Food Industry
In closed CIP circuits with centrifugal pumps, excessive foam is undesirable — it causes pump cavitation, reduces turbulence and thus mechanical action, and can lead to false readings when measuring conductivity for process control. That is why CIP formulations use low-foam nonionic surfactants (EO/PO copolymers) instead of the classic anionic surfactants used in manual cleaning.
Disinfection and Sanitation
Cleaning and disinfection are two distinct, sequential steps. Cleaning removes visible dirt and organic material from a surface. Disinfection then reduces the number of viable microorganisms to a safe level. Without thorough prior cleaning, disinfection is significantly less effective — residual fat or protein physically protects microorganisms from contact with the active substance.
Main Classes of Disinfectants
QAC / Benzalkonium chlorid (kvarterní amoniové sloučeniny)
Mechanism: Disrupt the cell membrane of microorganisms. Good stability, non-corrosive, but lower efficacy against enveloped viruses and spores.
Use: Surface disinfection, food industry, healthcare
Peroctová kyselina (kyselina peroctová, PAA)
Mechanism: A strong oxidizing agent, highly effective against bacteria, viruses, spores, and biofilms. Decomposes into harmless oxygen, water, and acetic acid.
Use: CIP disinfection, beverage industry, bottling plants
Peroxid vodíku (H₂O₂)
Mechanism: Oxidative mechanism, forms free radicals that damage cellular structures. Often combined with silver ions for stabilization and synergy.
Use: Fogging, air and surface disinfection, pharmaceutical industry
Chlorové přípravky (chlornan sodný, chloramin)
Mechanism: Oxidation of cellular components, very broad spectrum of activity including viruses. Rapid inactivation, but sensitive to organic load and lower stability.
Use: Water sanitation, surface disinfection, food operations
Alkoholové dezinfekční prostředky (ethanol, isopropanol)
Mechanism: Protein denaturation and disruption of the lipid membrane. Fast-acting, highly volatile — suitable for surfaces that cannot be rinsed.
Use: Hand disinfection, small tools, electronics
Contact Time, Concentration, and Log Reduction
The efficacy of disinfection is expressed as log reduction — the decrease in the number of microorganisms in orders of ten. European standards EN 1276 (bactericidal efficacy for the food, industrial, and domestic sectors) and EN 13697 (bactericidal and fungicidal efficacy on non-porous surfaces) define the test conditions and required level of reduction, typically at least 5-log (99.999%) within a defined contact time.
| Disinfectant | Typical Concentration | Contact Time | Log Reduction (per EN) |
|---|---|---|---|
| QAC (benzalkonium chlorid) | 0,05–0,2 % | 5–15 min | 5 log (EN 1276) |
| Peroctová kyselina | 0,1–0,3 % | 1–5 min | 5 log, virucidní/sporicidní |
| Peroxid vodíku | 0,5–3 % | 5–15 min | 5 log (EN 13697) |
| Chlornan sodný | 100–200 ppm aktivního Cl | 1–10 min | 5 log, rychlé působení |
| Ethanol 70% | 70 % obj. | 30 s–1 min | 5 log, rychlý odpar |
Values are indicative
The actual concentration and contact time are always governed by the specific approved product and its label/SDS — the values in the table serve as an order-of-magnitude guide, not as binding usage instructions for any specific product.
Metal Degreasing and Machining
Before surface treatment (painting, powder coating, electroplating) or welding, a metal surface must be free of all oils, pastes, and preservation agents — even a thin oil film prevents coating adhesion or causes weld defects (porosity, cracks).
Aqueous Degreasing Agents Replace Chlorinated Solvents
Traditional vapor degreasing with chlorinated solvents (trichloroethylene, perchloroethylene) has largely been replaced in recent decades by aqueous alkaline degreasing agents due to legislative restrictions (classification as a category 2 carcinogen, restrictions under REACH Annex XVII) and rising hazardous waste disposal costs.
Modern aqueous degreasing baths combine an alkaline component (NaOH, KOH, silicates) with nonionic and anionic surfactants that emulsify oils and allow them to be flushed away. They are applied by immersion, spraying, or ultrasonic cleaning, often at a temperature of 40–70 °C.
Corrosion Inhibitors in Degreasing Formulations
After degreasing, the metal surface is left without a protective layer of oil and is therefore prone to flash rust, especially on steel. Quality degreasing formulations therefore contain temporary corrosion inhibitors (e.g., borates, amines, benzotriazole for copper), or the degreased part is immediately processed by the next operation (phosphating, painting). For aluminum, specific inhibitors (silicates, gluconates) are additionally used to suppress alkali etching.
Legislation — Biocidal Products Regulation and REACH
Industrial cleaning and disinfection agents are subject to two key regulatory frameworks in the EU, which both buyers and suppliers must know:
Nařízení o biocidních přípravcích BPR (EU 528/2012)
Regulates the placing on the market of disinfectants (product type 2 and 4 under BPR — disinfectants for the private and public sector, and for the food and feed industry, respectively). The active substance must be approved at EU level, and the product itself must undergo authorization in the member state.
REACH (ES 1907/2006)
All chemical substances placed on the EU market above 1 t/year must be registered. Suppliers of industrial cleaning agents are required to provide an up-to-date safety data sheet (SDS) and hazard classification information under CLP.
CLP (ES 1272/2008)
Classification and labeling — strong alkalis and acids are classified as corrosive (Skin Corr. 1), oxidizing disinfectants as oxidizing. Containers must carry the corresponding hazard pictograms and H-statements.
Bezpečnostní listy (SDS) a expoziční limity
An SDS under Annex II of REACH must be available for every product. For substances with workplace exposure limits (OEL, PEL) — e.g., NaOH, phosphoric acid — the employer must ensure exposure limits are met and appropriate PPE is provided.
Nařízení o detergentech (ES 648/2004)
Surfactants used in cleaning formulations must meet biodegradability criteria (OECD 301 test, min. 60% mineralization). The label must list ingredients above the specified threshold values.
What to verify before purchasing a disinfectant
Verify that the active substance is listed among the approved active substances under BPR for the given product type (PT2/PT4), that the product has valid authorization for the Czech or European market, and that the supplier provides an up-to-date SDS with declared efficacy according to the relevant EN standard (EN 1276, EN 13697, or EN 14675 for food operations).
How to Choose the Right Cleaning Agent
Choosing the right chemistry is a decision-making process with several sequential steps. We recommend proceeding systematically:
1. Identify the type of soil
Organic (fat, protein) → alkaline chemistry or enzymes. Inorganic (limescale, rust) → acidic chemistry. Mixed → two-phase CIP process.
2. Choose the chemistry and concentration
Based on soil type and surface sensitivity — strong alkali/acid for resistant materials (stainless steel), mild/neutral for sensitive ones (aluminum, plastics).
3. Determine the process temperature
Higher temperature speeds up saponification and dissolution, but increases the risk of protein burn-on and energy demand. Enzymes require lower temperature (30–50 °C).
4. Choose the application method
Spraying for large areas, dipping for small parts, CIP for closed circuits, foam cleaning for vertical surfaces with longer contact time.
5. Verify material compatibility
Stainless steel tolerates most chemistries. Aluminum, galvanized sheet, and rubber seals require milder agents or specific inhibitors — verify in the SDS and technical data sheet.
6. Plan the disinfection step
If microbiological safety is required, follow cleaning with a validated disinfection step with proven log reduction according to the EN standard.
7. Verify legislative compliance
Check the SDS, CLP classification, the BPR status for disinfectants, and the availability of supplier technical support.
Frequently Asked Questions
What is the difference between cleaning and disinfection?+
What is Sinner's circle and why is it important for CIP?+
What pH should an alkaline cleaning agent have for degreasing?+
What does log reduction mean for disinfectants?+
What are the main phases of the CIP process?+
How do I choose a cleaning agent based on material type?+
Looking for a Specific Cleaning or Disinfection Agent?
GCG Group supplies alkaline, acidic, neutral, and enzymatic cleaning agents and disinfectants for the food industry, mechanical engineering, and facility management. Samples on request, technical support, individual pricing.