The control of the number of dust particles in the clea […]
The control of the number of dust particles in the clean room, and the environmental control and daily maintenance of the air shower room in the clean room are very important. The air purification system plays a very key role. When the air cleanliness requirement for injection production is 100, the vertical and horizontal unidirectional flow patterns are used, and the airflow speed is greater than 0.25 m/s and 0.35 m/s; when the air cleanliness is required to be 10,000 and 100,000, use Non-unidirectional flow, air exchange frequency is greater than 25 times/hour and 15 times/hour respectively (300,000 air exchange frequency is not less than 12 times/hour), in order to take away the dust and dust generated in the production process in time and maintain a clean room environment Cleanliness.
Clean rooms are divided into biological clean rooms and non-biological clean rooms. The air purification system of biological clean room must be operated continuously; the air purification system of non-biological clean room should be turned on 4 hours in advance. The dust particle counter used to detect dust particles is carried out after buffering for 0.5 to 1 hour after environmental sanitation. In order to avoid man-made pollution, there are only two persons in the clean room during static testing. The key control points should be dynamically monitored during the production process of injections. Control of microbial content. The control of the microbial content in the clean room environment still relies on good air purification system facilities, and its filtration efficiency can reach 99.9% to 99.99% to filter out bacteria and dust in the air. In production, the temperature in the clean room is strictly controlled at 18～26℃, and the relative humidity is controlled at 45%～65% to destroy the growth conditions that are conducive to bacteria, plus the cleaning and disinfection of disinfectant. Regarding the daily disinfection of the disinfectant, after every day of production, use 75% ethanol or 2‰ neocerin solution to wipe the machine, desktop, doors and windows, automatic air shower, purification workbench, clean shed, FFU fan filter unit, wall, etc. 3%～5% of Lysurer wipes and disinfects the floor. After every 3 days of production, use 75% ethanol or 2‰ neocerin solution to wipe and disinfect the surfaces of all facilities, ceilings, and lighting in the clean room, and 3% to 5% of Lysurer to disinfect the ground.
Strictly controlling the pressure difference between the clean room and the adjacent room is also an important part of ensuring the air cleanliness of the production room. The pressure difference between the clean room of different cleanliness and the clean area and the non-clean area should be greater than 5 Pascals, the pressure difference between the clean area and the outdoor should be greater than 10 Pascals, and the opening and closing of the supply air, return air and exhaust air flow should be connected Lock and operate in sequence, which can avoid air backflow and reduce the pollution of clean room environment by low-level dust. Before each production and after a certain production cycle, the number of dust particles in the clean room after cleaning must be tested under static conditions to evaluate and grasp the content of dust particles in the clean room.
The purpose of environmental control and daily maintenance of the air shower room in the clean room is to kill the bacterial propagule produced during the production process and control the microbial content in the clean room. These measures can only control the amount of bacteria and the types of bacteria in the clean indoor air. If there are more molds, you must first spray the room with 5% carbolic acid, and then fumigate with formaldehyde to achieve sterile effect, and only in this way can it be killed Bacteria, mixed bacteria spores. At the end of each production cycle, before the next cycle of production, the clean room with aseptic requirements shall be disinfected with disinfectant solution. After the number of dust particles in the clean room meets the requirements, the clean room is fumigated with formaldehyde gas. From the long-term test results See, this environmental sterilization method works well.
Formaldehyde gas sterilization technology. Formaldehyde fumigation not only has a good sterilization effect on molds that are not easy to kill, but also has a better killing effect on bacterial spores in the environment. Attention should be paid to the operation of formaldehyde fumigation: firstly, ensure that the room temperature is above 35℃ and the relative humidity is above 60%; secondly, ensure that the amount of formaldehyde reaches the ratio of room volume 10g/m3; in addition, the room disinfection time is not less than 12 hours; it is especially worthwhile It is reminded that the same proportion of ammonia should be used for neutralization before formaldehyde replacement, which will minimize the harm to the human body and the pollution to the environment. In order to prevent bacteria from developing resistance to formaldehyde, it is better to use ozone to alternate.