RKI Cleaning and Disinfection

Cleaning and disinfection remove contaminants and reduce the microbial load to a level that allows instruments to be safely processed further – they form the foundation of every standards-compliant sterile supply reprocessing cycle. This step is mandatory for all instruments requiring reprocessing. The KRINKO recommends automated, validatable processes because they are reproducible and verifiable.

1Three Methods – One Goal

Cleaning & disinfection can be carried out in three ways:

1. Manual (chemical) – by hand using cleaning and disinfection solutions.
2. Ultrasonic cleaner (supportive cleaning) – uses cavitation to loosen contaminants even in delicate or hard-to-reach structures; does not replace subsequent disinfection or automated reprocessing in a washer-disinfector.
3. Automated in a washer-disinfector / WD (thermal) – cleans and disinfects in a validated, documented process.

2Which Device for Which Risk Category?

3Manual Cleaning & Disinfection

Cleaning: disassemble any instruments that can be taken apart and open all joints. Place them in a tray with a suitable cleaning solution prepared according to the manufacturer's instructions. Clean mechanically with plastic brushes – no abrasive agents or scouring pads (risk of damage). Then rinse thoroughly with water until no cleaning-solution residues remain.

Disinfection: immerse in a freshly prepared disinfection solution that is proven to be bactericidal (including mycobacteria), fungicidal and virucidal and is listed in the current VAH list with the required spectrum of activity. Observe the contact time exactly as specified by the manufacturer, then rinse thoroughly again.

Drying: allow to drip-dry and then dry completely with a lint-free cloth or medical-grade compressed air; drying must prevent recontamination – residual moisture jeopardises subsequent sterilisation.

4Automated Processes

Ultrasonic cleaner: uses cavitation to loosen contaminants even in hard-to-reach areas; ideal as a supplement or for delicate instruments. Do not overload the basket; ensure all instruments are fully submerged.

Washer-disinfector (WD): cleans and thermally disinfects in a validated programme. The measure of disinfection efficacy is the A0 value (guideline value A0 ≥ 3000 for critical instruments). The process is fully documentable and therefore ideal for meeting traceability requirements – record your batch documentation in just a few clicks with the free ClavioSoft.

Key Additional Points per RKI & Standards

These points are frequently overlooked in practice but are essential for correct and legally compliant implementation:

• Pre-treatment / pre-cleaning at the point of use: Gross soiling (blood, secretions, tissue residues) should be removed as soon as possible after use to prevent drying; cleaning should follow promptly. Pre-cleaning agents and methods must be compatible with subsequent reprocessing steps.Source: KRINKO/BfArM 2012, Section 2.2.1 (Pre-treatment, collection, pre-cleaning)
• No fixating procedures before cleaning: No fixating procedures may be applied before cleaning – in particular no heat and no aldehydes – as these fix proteins/blood and impair cleaning. Fixation of residues must also be avoided during disinfection; therefore: clean first, then disinfect.Source: KRINKO/BfArM 2012, Section 2.2.1 ('Avoidance of fixating procedures such as the application of heat or aldehydes before cleaning') and 2.2.2 (fixating properties of aldehyde, alcohol, peracetic acid, temperatures > 55 °C)
• Final rinse with purified water (demineralised water): The final rinse must be performed with water of suitable quality; demineralised (DI) water is recommended to avoid deposits and crystallisation on the instrument. The final-rinse water must be free of facultatively pathogenic micro-organisms (microbiologically at least drinking-water quality).Source: KRINKO/BfArM 2012, Section 2.2.2 (Requirements for final-rinse water: freedom from facultatively pathogenic micro-organisms, demineralised water recommended)
• Validation and standard operating procedures for manual reprocessing: Manual cleaning and disinfection procedures must also be performed according to documented standard operating procedures using agents that have been tested for efficacy and material compatibility and must be validated. Critical process parameters (e.g. concentration, temperature, contact time, rinsing steps) must be defined and verified through periodic checks; the reprocessing instructions provided by the manufacturer (DIN EN ISO 17664) must be observed. Standard operating procedures and the associated documentation can be managed conveniently in one place with the free ClavioSoft.Source: KRINKO/BfArM 2012, Section 2.2.2 (manual procedures according to documented standard operating procedures, validated; critical process parameters to be defined and periodically reviewed); MPBetreibV
• Visual cleanliness inspection after cleaning: Effective sterilisation can only be guaranteed with clean instruments. After cleaning and disinfection, every instrument must be visually inspected for cleanliness (no visible residues, encrustations or deposits), integrity and function; where particularly high requirements apply, optical magnification aids may be used. Instruments that are not perfectly clean must be reprocessed.Source: KRINKO/BfArM 2012, Section 2.2.2 ('Effective sterilisation can only be guaranteed with clean medical devices'; visual inspection, magnification aids if applicable for critical C)
• Qualified personnel: Cleaning and disinfection may only be performed by personnel with documented specialist knowledge (instrument science, hygiene/microbiology, risk assessment). For critical-B instruments, proof of recognised training of the person carrying out the reprocessing is additionally required.Source: KRINKO/BfArM 2012, Annex 6 'Specialist knowledge of personnel'; Table 1, Footnote 4 ('Proof of recognised training'); MPBetreibV
• Occupational safety / personal protective equipment: During manual reprocessing in the contaminated zone, personal protective equipment must be worn (suitable protective gloves, safety goggles, protective clothing), and adequate room-air quality as well as separation of clean/contaminated areas must be ensured.Source: KRINKO/BfArM 2012, Section 2.2.1/2.2.2 ('Protective clothing, safety goggles, suitable gloves; room-air quality', TRBA 250)
• Differentiating A0 guideline values (A0 600 / A0 3000): The A0 value describes the efficacy of thermal disinfection in the washer-disinfector. Two guideline values are common: A0 600 for instruments without special requirements, and A0 3000 for critical instruments or those contaminated with highly tenacious pathogens. The target value depends on the risk assessment and manufacturer specifications. This article has so far referred only to A0 ≥ 3000.Source: DIN EN ISO 15883-1 (A0 concept: guideline values A0 600 / A0 3000). Note: The A0 values are defined in DIN EN ISO 15883, not in the KRINKO full text.

Required Equipment, Consumables & Accessories

Checklist for this processing step – items you should have ready (shopping list):

Templates & References

1. KRINKO/BfArM 2012, Bundesgesundheitsbl. 55:1244–1310 – Section 2.2.2.
2. DIN EN ISO 15883 (washer-disinfectors, A0 value); VAH list.
3. MPBetreibV § 8; Dental Chamber standard operating procedures.