The standard specification for air used in aseptic workshop mainly involves the cleanliness, temperature and humidity, air flow organization, air change frequency, static pressure difference and air filtration system. The following is a detailed summary of these criteria:
1. air cleanliness
- according to the ISO 14644-1 international standard, the air cleanliness level in aseptic workshops ranges from 1 to 9. The smaller the number, the higher the cleanliness. For example, ISO level 5 (100) requires no more than 3520 particles of 0.5 microns or more per cubic meter of air, while ISO level 1 (10) requires no more than 35 particles.
- In the GMP aseptic workshop, the air cleanliness level is usually divided into four levels: A, B, C and D, of which A is the highest cleanliness level, which is suitable for high-risk operation areas, such as filling areas.
- For the food industry, aseptic shop air cleanliness levels may be ISO 7 or higher, depending on food processing requirements.
2. temperature and humidity control
- the temperature in the aseptic workshop should be controlled within an appropriate range to ensure the stability and quality of the production process. Generally, the temperature is controlled at 18-26 degrees Celsius and the humidity is controlled at 45-65%.
- If the production process of the product itself has special requirements for temperature and humidity, it is necessary to set the appropriate temperature and humidity according to the requirements of the product.
3. airflow organization
- the air flow organization in the aseptic workshop should be designed as unidirectional flow or laminar flow to reduce the suspension and diffusion of particles in the air. Generally, the air supply and return vents of the clean room should be reasonably arranged to form a uniform airflow.
- In the-level clean area of the GMP aseptic workshop, the air should be filtered by a high-efficiency filter and then transported in a unidirectional flow (laminar flow) to meet the needs of air blowing the suspended particles in the potting area in the form of a piston.
4. ventilation rate
- the number of air changes in the aseptic workshop should be determined according to the cleanliness level and production requirements. For example, the number of air changes in a 100,000-level aseptic workshop is generally 15-20 times per hour; the number of air changes per hour in the 10,000-level clean area is not less than 20 times; the number of air changes per hour in the 1,000-level clean area is not less than 50 times.
5. static pressure difference
- aseptic workshop should maintain a certain positive pressure, in order to prevent the outside unclean air into the clean workshop caused by cross contamination. Generally, the static pressure difference between adjacent rooms with different air cleanliness levels should be greater than 5Pa, and the static pressure difference between the clean room and the outdoor atmosphere should be greater than 10Pa.
6. air filtration system
- high-efficiency particle air filters (HEPA) or ultra-high-efficiency particle air filters (ULPA) are the core equipment in aseptic workshops. They can remove particles from the air and ensure the cleanliness of the air. Depending on the level of purification, the efficiency of the filter and the frequency of replacement will vary.
7. other requirements
- clean lamps shall be used for lighting in aseptic workshop to reduce dust generation. The power system should be stable and reliable to avoid production interruption caused by power failure.
- The workshop shall be equipped with monitoring equipment such as particle counter and temperature and humidity meter to detect the environmental parameters regularly. At the same time, a strict maintenance plan should be established to regularly clean and maintain the air filtration system, equipment and facilities.
- Personnel and materials entering the sterile workshop should undergo strict cleaning and disinfection procedures. Personnel should wear aseptic clothing, masks, gloves and other protective equipment, and materials should enter through the transfer window or airlock chamber.
To sum up, the gas standard specification of aseptic workshop is a comprehensive requirement system, covering air cleanliness, temperature and humidity, airflow organization, ventilation frequency, static pressure difference, air filtration system and other aspects. The strict implementation of these requirements is essential to ensure the stability of the production process and product quality.
