Ultra-clean workbench principle, use and maintenance

Ultra-clean workbench principle , use and maintenance

A clean bench is a facility that provides a sterile operating environment for laboratory work to protect the experiment from the external environment while providing some level of protection to the external environment from contamination and protecting the operator. Compared to a simple sterile cover, the clean bench has the advantage of allowing the operator to move freely, easily reach anywhere in the operating area, and have a higher overall level.

(I) Principle The clean environment of the clean bench is formed in a specific space where clean air (inlet air) flows in a set direction. Divided by the direction of the airflow, the existing ultra-clean workbench can be divided into vertical, from the inside to the outside and from the side. Considering the quality of operation and the impact on the environment, it is superior in vertical mode. The clean air supplied by the air supply filter plate descends through the operation area at a specific speed, is separated in the middle of the operation area, is sucked away by the front air suction hole and the rear suction window, and the air sucked in the front and rear portions at the lower portion of the operation area is mixed. Together, and pumped into the rear positive pressure zone by a blower, in the upper part of the machine, 30% of the gas is discharged from the top through the exhaust filter plate, and approximately 70% of the gas is re-entered into the operating zone through the oxygen supply filter plate. To supplement the air discharged from the exhaust port, the same volume of air is replenished from the room air through the operating port. This air will never enter the operating area, just forming an air barrier.

(2) The ultra-clean workbench where the commissioning is located has undergone rigorous testing before leaving the factory to ensure normal use. But this is not to say that the manufacturer's test can replace the operator to perform the necessary inspection and debugging before use. Because the environment in which the ultra-clean workbench is located is different, only the proper inspection and debugging can maximize the role of the equipment. A better environment should be selected for the machine before commissioning. It is best to place it in a sterile room with an air disinfection facility. If conditions are not available, the machine should be placed in a clean, clean room. Adjust the height of each foot to ensure a safe and level of operation. The power supply of the ultra-clean workbench should use a special circuit to avoid the change of air flow rate caused by the overload of the circuit. Compared to the simple aseptic cover, the clean bench has a standard configuration that allows the operator to move freely, easily reach the operating area, and the UV lamp and lighting fluorescent lamp are standard on the clean bench. The blower provides the power of air flow. Whether these components work properly is clear at a glance. The most difficult and important thing is to inspect the air filter plate and its tightness, which is directly related to the normal use of the machine. The simplest method of examination is the nutrient agar plate method. Newly purchased and unused ultra-clean workbench, in addition to UV light, etc., it is best to fumigation, then put an open nutrient agar plate in the four corners and the center of the operating area when the machine is in working condition. After two hours, the lid was placed and placed in a 37 ° C incubator for 24 hours to calculate the number of colonies. The average number of colonies per plate must be less than 0.5.

(3) Use the ultra-clean workbench to apply ultraviolet light for 30-40 minutes before use, and check that all open doors and windows around the operating area are in working position. The operation is preferably carried out at the center of the operating area, which is a safer area in design. You should have a preliminary understanding of the experimental materials before proceeding, and understand the performance and safety level of the equipment you are using. Strictly enforce laboratory safety procedures. The use of specific pathogens in any ultra-clean workbench must be evaluated for safety. If the test material causes environmental pollution to the surrounding environment, it should be avoided in the model without the exhaust filter, because operating in flowing air is no different from dispersing. Any advanced equipment does not guarantee the success of the experiment. The use of the ultra-clean bench of the animal quarantine laboratory is aimed at sterility and avoiding cross-contamination, so skilled operation and clear sterility essentials are essential.

(4) Maintenance The ultra-clean workbench is a relatively precise electrical equipment, which is very important for its regular maintenance and maintenance. First of all, we must keep the indoors dry and clean. The humid air will not only rust the manufacturing materials, but also affect the normal operation of the electrical circuit. The humid air is also conducive to the growth of bacteria and mold. A clean environment also extends the life of the filter plate. In addition, regular cleaning of equipment is an important part of normal use. Cleaning should include routine cleaning and periodic handling before and after use. When fumigation, all gaps should be completely sealed. For example, the type of ultra-clean workbench with movable baffle cover at the operation port can be sealed with plastic film. The filter plates and UV germicidal lamps of the ultra-clean workbench have a calibrated service life and should be replaced on schedule.