Cleanrooms are a fundamental supporting industry with a wide range of applications. They are currently used in numerous industries, including electronics, semiconductors, optoelectronics, precision manufacturing, medicine, aerospace, and automotive painting. Let’s discuss how cleanroom air cleanliness levels are classified.
Air cleanliness refers to the level of suspended particulate matter in the air within a clean environment. Generally, higher dust concentrations indicate lower air cleanliness, while lower dust concentrations indicate higher air cleanliness. Air cleanliness levels are determined by the maximum allowable number of particles per cubic meter of air. Air cleanliness is measured using a particle counter. Class 100 represents the number of dust particles allowed per cubic inch of air. Higher class numbers indicate lower cleanliness. Cleanroom class standards (US Federal Standard 209E) generally rank below Class 300,000 for enclosed rooms. For open rooms, the rating depends on the air quality of each space.
Cleanroom cleanliness and the consistent stability of pollution control are the core criteria for evaluating cleanroom quality. These standards are divided into several grades based on factors such as the regional environment and the degree of purification. Commonly used are international standards and domestic regional industry standards. Some well-known cleanroom engineering companies, in addition to established standards, also implement their own purification specifications that exceed international standards, resulting in purification capabilities and environmental adaptability far exceeding those of international brands.
Specific workshop air purification grades are as follows:
Class 300,000; Maximum allowable microbial count: 1,000 airborne bacteria/cubic meter; Applicable to: Pill and granule packaging workshops.
Class 100,000; Maximum allowable microbial count: 500 airborne bacteria/cubic meter; Applicable to: Injection concentration workshops.
Class 10,000; Maximum allowable microbial count: 100 airborne bacteria/cubic meter; Applicable to: Small-volume injection filling workshops and final processing workshops for packaging materials that come into direct contact with pharmaceuticals.
Class 100; Maximum allowable microbial count: 5 airborne bacteria/cubic meter; Applicable to: Large-volume injection filling workshops. Cleanroom Testing Scope: Cleanroom environmental rating assessment and project acceptance testing, including food, cosmetics, bottled water, milk production workshops, electronics production workshops, GMP workshops, animal laboratories, biosafety laboratories, biosafety cabinets, clean benches, dust-free workshops, and aseptic workshops.
Cleanroom Cleanliness Testing for Hospital Clean Operating Rooms (12 items): Number of air changes, static pressure difference, air cleanliness, temperature, humidity, settling bacteria (static), noise, illumination, floating bacteria, HEPA filter leak detection, self-cleaning time, and minimum fresh air volume.
The significance of a clean environment can be categorized into four aspects:
1. Removal of suspended particles, microorganisms, and gaseous pollutants in a clean environment through filtration and airflow direction.
2. Controlling the temperature and humidity in a clean environment reduces the activity of pollution sources within the operating environment to ensure clean operations.
3. Through specialized building design, auxiliary indicators such as noise, illumination, and vibration amplitude are ensured to be unaffected by the external environment and meet operational requirements.
4. Design adjustable air volume and return air to maintain positive and negative pressure differentials with non-clean areas, preventing the spread of pollutants into clean environments.
With the gradual implementation of Good Manufacturing Practices (GMP) regulations in my country’s pharmaceutical industry, clean air technology is widely used in pharmaceutical companies, hospital preparation rooms, operating rooms, and other medical and healthcare sectors. Whether during the cleanroom construction and acceptance phase or during operation and maintenance, specific testing procedures are required to ensure the clean environment meets the requirements of production and R&D.
