As a key equipment for providing a local high-cleanliness environment, the operational stability and purification effect of laminar flow hoods directly depend on standardized daily maintenance and care. Scientific maintenance and care not only extend the service life of equipment but also ensure that it continuously meets the cleanliness requirements of various application fields. The following are detailed daily maintenance and care methods:
I. Daily inspection and cleaning
1. Daily surface cleaning: Every day, use a clean lint-free cloth dipped in neutral detergent to gently wipe the outer shell, operating table surface and observation window of the laminar flow hood. Avoid using highly corrosive cleaning agents to prevent damage to the surface coating and seals of the equipment. After cleaning, wipe it clean with pure water to ensure there is no residue of cleaning agents and to prevent the volatilization of residual substances from contaminating the clean area.
2. Operation status check: Before starting the machine every day, check the power supply of the equipment and the operation status of the fan, and observe whether the fan has any abnormal noise, vibration or other conditions. At the same time, check whether the indicator lights, pressure gauges (if any), and other instrument displays are normal. Only after confirming that the equipment is in a normal standby state should it be started and operated.
3. Clean air flow monitoring: By observing the air flow indicator devices inside the laminar flow hood (such as silk thread, smoke generator auxiliary detection), check daily whether the air flow is uniform, stable, and free of vortices or air flow interruption. If abnormal air flow is detected, the cause should be investigated promptly.
Ii. Maintenance of Core Components
1. Maintenance of high-efficiency filters (HEPA/ULPA) : High-efficiency filters are the core of the purification effect of laminar flow hoods and require regular maintenance. ① Regular inspection: Use a particle counter to test the cleanliness of the air outlet of the filter every 3 to 6 months. If the test results do not meet the design requirements (such as Class 100 or class 1,000 cleanliness standards), it should be replaced in a timely manner. ② Differential pressure monitoring: Pay attention to the differential pressure gauge of the filter every day. When the differential pressure exceeds 20% to 30% of the initial differential pressure, it indicates that the filter is severely clogged and should be replaced immediately. ③ Precautions for replacement: When replacing the filter, it should be done in a clean environment. Wear dust-free gloves and a mask. Avoid direct contact with the filter paper by hand. Ensure a tight installation seal to prevent air leakage.
2. Fan maintenance: The fan serves as the power source for the airflow circulation of the laminar flow hood and requires regular maintenance. ① Regular lubrication: Add an appropriate amount of special lubricating oil to the fan bearings every 6 to 12 months to reduce bearing wear and lower operating noise. ② Clean the fan impeller: Clean the fan impeller once a year to remove the accumulated dust and debris on it to prevent dust accumulation from affecting the fan’s air volume and operational stability. ③ Troubleshooting: If the fan experiences problems such as decreased speed, increased noise, or intensified vibration, it should be shut down immediately for inspection. If necessary, contact professional personnel for repair or replacement of fan components.
3. Maintenance of seals: The seals of laminar flow hoods (such as sealing strips and sealants) can prevent external contaminated air from seeping in and need to be inspected regularly. Check the sealing parts every month for any signs of aging, cracking or falling off. If any sealing failure is found, replace the sealing parts in time and reapply sealant to ensure the sealing performance of the equipment.
Iii. Regular in-depth maintenance
1. Internal cavity cleaning: Conduct a deep cleaning of the internal cavity of the laminar flow hood every 1-2 months. First, turn off the power supply. Remove the movable parts (such as the operation table and the deflector plate). Use a lint-free cloth dipped in neutral detergent to thoroughly wipe the inner walls of the cavity, the deflector structure and other parts. Then rinse it clean with pure water. Finally, dry it with a sterile dry cloth to ensure that there is no dust or debris remaining in the cavity.
2. Electrical System Inspection: Conduct a comprehensive inspection of the equipment’s electrical system every six months, including wires, plugs, sockets, and electrical components inside the control cabinet, etc. Check whether the wires are aged or damaged, and whether the electrical components are loose or overheated. If any problems are found, repair or replace them in time to avoid electrical faults causing safety hazards.
3. Overall performance testing: Every year, professional testing institutions are invited to conduct a comprehensive test on the overall performance of the laminar flow hood, including indicators such as cleanliness, air velocity uniformity, pressure difference, and noise, to ensure that all performance aspects of the equipment comply with relevant standards and usage requirements.
Iv. Usage and Maintenance Contraindications
1. It is strictly prohibited to disassemble the equipment components during the operation of the laminar flow hood to avoid disrupting the stability of the airflow and causing personal injury.
2. Do not place heavy objects on the top of the laminar flow hood or on the operation table to prevent deformation or damage to the equipment.
3. It is strictly prohibited to store volatile, corrosive or flammable and explosive items near the laminar flow hood to avoid polluting the clean environment or causing safety accidents.
During the maintenance process, if any unsolvable faults occur, it is strictly prohibited to disassemble the core components (such as fans and filters) without authorization. Instead, contact the equipment manufacturer or professional maintenance personnel promptly for handling.
When the laminar flow hood is not in use for a long time, the power supply should be turned off, and the equipment should be covered with a dust cover to prevent dust accumulation and contamination. At the same time, the machine should be started and run for 30 minutes regularly (every three months) to check the equipment status and prevent component aging.
In addition, it is also crucial to establish a complete maintenance record ledger. It is necessary to record in detail the time, content, detection data, replacement of parts and other information of each maintenance, so as to trace the operating status of the equipment and provide a reference basis for subsequent maintenance.
