How to clean microorganisms on the walls of clean rooms

The walls in modular clean rooms are one of the key parts for maintaining a clean environment. Microbial contamination often spreads through dust accumulation on the walls, air flow, etc., affecting product quality. Cleaning microorganisms on the walls is not only to comply with industry standards, but also a necessary measure to ensure laboratory safety and product compliance. This article will discuss in detail how to effectively clean microorganisms on the walls of clean rooms to ensure that the clean environment meets relevant standards.

Understanding microbial contamination on the walls of clean rooms

1. Sources of microbial contamination

The sources of microbial contamination mainly come from air, equipment, personnel, etc. Common microorganisms on the walls of clean rooms include bacteria, fungi, molds, etc. According to the ISO 14644-1 standard, the number of these microorganisms should be limited in clean rooms to ensure that the environment meets the requirements of the specified level.

• Source: air, equipment, personnel

• Common microorganisms: bacteria, fungi, mold

• Standard requirements: Ensure that the number of microorganisms does not exceed the standard

2. The impact of microorganisms on clean rooms

Microbial contamination not only affects the cleanliness of clean rooms, but may also cause product quality problems, especially in industries that are sensitive to microorganisms such as pharmaceuticals and Semiconductors. By controlling the microorganisms on the walls, the risk of cross-contamination in the production process can be effectively reduced.

• Impact: May cause cross-contamination and damage product quality

• Sensitive industries: pharmaceuticals, semiconductors

• Control measures: clean Walls to reduce contamination

3. The importance of microbial monitoring

According to the international standard ISO 14698, microbial monitoring should be carried out regularly, including sampling and analysis of wall surfaces, air and equipment. Monthly surface sampling should be no less than 1

location per square meter to ensure that potential microbial problems are discovered in a timely manner.

Standards and methods for wall cleaning

1. Choose a suitable detergent

When cleaning the walls of clean rooms, disinfectants that meet industry standards should be selected, commonly used ones include chlorine-containing disinfectants, hydrogen peroxide solutions, etc. Cleaning agents should comply with ISO 9001 or ISO 14001 certification requirements to ensure effective removal of microorganisms without causing damage to wall materials.

2. Cleaning frequency and procedures

The frequency of wall cleaning is determined by the cleanroom grade and industry requirements. For ISO 5 Cleanrooms, a comprehensive cleaning should be performed once a week to ensure that the walls are dust-free and sterile. Wet wiping can be used during the cleaning process to avoid secondary contamination caused by dry wiping.

• Cleaning frequency: ISO 5 clean once a week

• Cleaning method: Wet wiping to avoid contamination caused by dry wiping

3. Requirements for personnel and equipment for cleaning operations

When cleaning a modular cleanroom, it should be operated by trained staff using special cleaning tools such as dust-free cloths and cleanroom vacuum cleaners. Cleaning staff should wear appropriate clean clothing to prevent cross contamination.

Actual operation of wall cleaning

1. Steps for surface cleaning

When cleaning the wall, first wipe the wall with disinfectant wipes to remove surface dust and microorganisms. Afterwards, use a high-efficiency air (HEPA) vacuum cleaner to remove the dust near the wall to ensure that the wall is clean and sterile.

• Step 1: Wipe the wall with disinfectant wipes

• Step 2: Vacuum with a HEPA vacuum cleaner

• Effect: Surface cleaning, removal of microorganisms and dust

2. Precautions for dead corner cleaning

When cleaning the wall, pay special attention to the dead corner where the wall meets the ceiling, and the part where the lower part of the wall touches the ground. These areas are usually prone to dust and microorganisms and need to be cleaned intensively.

3. Disinfection after cleaning

After completing the wall cleaning, perform secondary disinfection and use a suitable disinfectant to cover the entire wall, especially the high-risk areas. This step is the key to ensure that the microorganisms are completely removed. It is recommended that the disinfection time is not less than 15 minutes.

Inspection and verification after wall cleaning

1. Surface microbial detection

After cleaning, the wall should be tested for microorganisms to verify the cleaning effect. According to ISO 14698, surface microbial sampling should be carried out by sterile wiping method, and the growth of bacteria and mold should be tested by culture medium.

2. Cleaning records and reports

After each cleaning, a cleaning record must be filled in, including information such as the cleaning date, disinfectant used, cleaning staff, and test results. The record must be retained for at least 12 months

for subsequent review and quality control.

Related standards and specifications

• ISO 14644: Modular cleanroom and related controlled environment standards

• ISO 14698: Microbial control and monitoring standards

• ISO 9001: Quality management system standards

• ISO 14001: Environmental management system standards

Through a scientific and systematic wall cleaning process, combined with standardized operation and verification methods, microbial contamination on the walls of the cleanroom can be effectively controlled, ensuring the long-term stable operation of the cleanroom in compliance with industry standards and quality requirements.