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Walking into a modern semiconductor wafer fabrication plant or a high-end biopharmaceutical workshop, one is greeted by fully equipped engineers, precisely maneuvering robotic arms, and an almost 'vacuum-like' clean environment. The low hum of the air purification system seems to tell a story of humanity's relentless pursuit of absolute cleanliness. This is the cleanroom—the cornerstone of modern high-end manufacturing.     Cleanroom: A Micron-Level Industrial Fortress A cleanroom, also known as a controlled environment room, is not simply a room that is cleaned physically, but a controlled environment created through precise engineering methods. Its core lies in controlling airborne dust particles, microorganisms, harmful gases, and other contaminants to extremely low concentration levels to meet the stringent requirements of specific manufacturing processes.     • Micron-level cleanliness standards: The cleanliness of a cleanroom follows international standards (such as ISO 14644-1), with levels ranging from ISO Class 1 (highest) to ISO Class 9. For example, in an ISO Class 5 cleanroom (equivalent to the former "Class 100" standard), the number of particles larger than 0.5 microns per cubic meter of air must not exceed 3,520. In contrast, the quantity of particles in the air of an ordinary urban environment can reach several million. In the field of chip manufacturing, when line widths enter the 3-nanometer era, even the tiniest dust particle can become a "lethal killer" causing product defects.   • Comprehensive control beyond cleanliness: In addition to particulate matter, a cleanroom must precisely control temperature, humidity, pressure differential, static electricity, and even vibration. For instance, semiconductor photolithography areas require temperature fluctuations to be controlled within ±0.1°C to prevent misalignment caused by thermal expansion and contraction; simultaneously, maintaining positive pressure inside the cleanroom can effectively prevent unfiltered dirty air from entering.   Core of the Design: Building a "Zero-Pollution" Ecosystem The design goal of a cleanroom goes far beyond simply "filtering the air"; it is about creating a dynamic ecosystem capable of continuously resisting and eliminating contamination. The core design principles are reflected in the following aspects:   • The Art of Airflow Organization: Airflow is the "blood" of a cleanroom. Designers use Computational Fluid Dynamics (CFD) simulations to optimize airflow paths, ensuring that clean air evenly "washes" the entire work area and rapidly removes contaminants. In the highest-grade clean areas, vertical unidirectional (laminar) flow is typically used, with clean air flowing from top to bottom like an "air piston" to remove pollutants with maximum efficiency.   • Sealing of Building Structures: The walls, ceilings, and floors of the workshop form the "skin" of the clean space. All materials must be smooth, non-dusting, dust-resistant, and corrosion-resistant, such as color steel panels, stainless steel sheets, and epoxy self-leveling floors. All joints require rounded treatments and reliable sealing, and all pipelines must be concealed to eliminate any dead corners where dirt could accumulate.   • Intelligent Dynamic Monitoring: Modern cleanrooms are a "smart living entity." By deploying laser particle counters, temperature and humidity sensors, and differential pressure meters, combined with a Building Management System (BMS), real-time 24/7 monitoring and automatic adjustment of environmental parameters can be achieved, ensuring that any minor anomalies are detected and addressed immediately.   Core Weapon: The 'Skynet' Built by Multi-Stage Filtration Equipment The key to achieving ultimate purification lies in a meticulously coordinated filtration equipment system, which functions like the 'super lungs' of a workshop, providing multiple layers of protection to ensure clean air.   • Primary and Medium Efficiency Filters (Pre-Filtration): This is the first line of defense in an air purification system. The primary filter (such as G4 grade) intercepts large particles above 5 microns, including dust and hair; the medium efficiency filter (such as F8 grade) further captures medium particles between 1–5 microns. Their main purpose is to protect the terminal high-efficiency filters and extend their service life.   • High-Efficiency/Ultra-High-Efficiency Filters (HEPA/ULPA): This is the 'heart' of a cleanroom. High-Efficiency Particulate Air (HEPA) filters can capture 99.97% of particles as small as 0.3 microns, while the more advanced Ultra-Low Penetration Air (ULPA) filters can capture even smaller particles. Installed at the end of the air supply system (such as in Fan Filter Unit (FFU), they are the final assurance that the air delivered to the cleanroom meets the required cleanliness level.   • Chemical Filters (AMC Control): In cutting-edge industries like semiconductors, controlling only particulate matter is far from sufficient. Gaseous molecular pollutants (AMC), such as acids and bases generated during processing, are equally critical. Chemical filters filled with activated carbon or other specialized media selectively adsorb these molecular-level pollutants, providing more comprehensive protection for the production process.     When air is purified to its extreme, it is no longer ordinary air but a special medium that carries the highest precision and strictest standards of modern industry. From the smartphones in our hands to life-saving vaccines, cleanrooms, with their 'invisible precision,' silently support the 'visible heights' of human technological civilization.

Clean air plays a crucial role in plant tissue culture and pharmaceutical technology development, and is the core foundation for ensuring experimental success, product quality, and production safety. Although the application scenarios in the two fields are different, their core logic is the same: maintaining a sterile or controlled environment by controlling airborne microbial and particulate pollution. Here's a breakdown of the role of clean air in these two key areas:   Ⅰ. The key role in plant tissue culture Plant tissue culture is a technology in which plant explants (such as stem tips, leaves, etc.) are inoculated into artificially prepared medium for culture under sterile conditions. Clean air is the first line of defense against pollution. 1. Reduce microbial contamination rate (core pain point)     The current situation is grim: According to statistics, the microbial contamination rate in plant tissue culture is as high as 15%-40%, of which bacterial contamination accounts for about 80%, followed by fungal contamination. Once contaminated, it will not only lead to the scrapping of the current batch of seedlings, but may also spread to the entire culture room, causing huge economic losses.   Airborne pollution: Airborne fungal spores (e.g., Penicillium, Aspergillus niger) and bacterial spores are the main sources of pollution. If these particles settle on the medium or explant incision, they will multiply rapidly at the right temperature and humidity.   The role of clean air:Blocking the transmission pathway: The high-efficiency air filtration system (HEPA or ULPA) removes particulate matter ≥ 0.3 μm in the air, directly cutting off the aerosol transmission path of fungal spores and bacteria.   Laminar flow clean bench efficiency: In inoculation operations, laminar flow clean benches rely on clean laminar air to form an "air barrier" to protect the operating area from external environmental interference. If the air intake is not clean, even if the wind speed reaches the standard, the sterility effect cannot be guaranteed.   2. Ensure the growth quality and genetic stability of tissue culture seedlings Hidden pollution prevention and control: Some endophytes or low-concentration microorganisms may not immediately cause turbidity of the culture medium, but they will secrete toxins or compete for nutrients, inhibit plant cell division and differentiation, and lead to slow growth, deformity and even death of tissue culture seedlings. Clean air minimizes this hidden pollution. Reliability of experimental data: In scientific research experiments, variable interference caused by air pollution can make experimental results irreproducible. The clean environment ensures the accuracy of experimental results, which is especially critical for genetic improvement and genetic engineering research.   3. Optimize environmental control strategies Dynamic sterility demand: Traditional UV or ozone disinfection has "human-machine separation" limitations and cannot sustain bacterial inhibition. Modern tissue culture rooms are more inclined to use air purification equipment with human-machine coexistence functions to achieve 24-hour planktonic bacteria and settled bacteria to meet the standards and ensure continuous cleanliness.   Ⅱ. The Key Role in Pharmaceutical Technology Development In the pharmaceutical field, clean air is not only a guarantee for the success of experiments but also a mandatory requirement under laws and regulations (such as GMP), directly affecting drug safety and patient health.   1. Compliance with GMP (Good Manufacturing Practice for Pharmaceutical Products) Regulatory Requirement: GMP standards worldwide (such as China GMP, EU GMP, and US FDA cGMP) strictly classify the cleanliness of the air in pharmaceutical environments (e.g., Grade A, B, C, D). Key Indicators: The number of suspended particles and microbiological limits (airborne microorganisms, settled bacteria, surface microorganisms) in the air must be strictly controlled. For example, in aseptic filling areas (Grade A), the number of particles ≥0.5 μm per cubic meter must not exceed 3,520, and no microorganisms should be detected.   2. Ensuring the Safety of Aseptic Preparations Protection of High-Risk Operations: During the production of aseptic drugs such as injections, vaccines, biological products, and ophthalmic preparations, any airborne particles or microorganisms entering the product may cause severe infection risks or even death. Prevention of Cross-Contamination: When developing and producing drugs with different active pharmaceutical ingredients (APIs), clean air conditioning systems (HVAC) control air pressure differences and directional airflow to prevent high-activity or sensitizing substances from spreading through the air to other areas, thereby avoiding cross-contamination.   3. Supporting Biotechnology and Cell Therapy Development Sensitivity of Cell Cultures: In the development of monoclonal antibodies, gene therapy vectors (such as viral vectors), and stem cell therapies, cells are extremely sensitive to the environment. Contamination of cell banks by mycoplasma, viruses, or fungal spores in the air can lead to the failure of an entire R&D project, resulting in losses of millions of dollars. Process Stability: A clean air environment helps maintain the stability of the surroundings of bioreactors, reducing abnormal cell metabolism due to environmental fluctuations and ensuring batch-to-batch consistency of drugs.   4. Extending Equipment Lifespan and Reducing Downtime Clean air reduces dust particle deposition inside precision instruments (such as filling machines, lyophilizers, and testing equipment), lowers equipment failure rates, decreases the frequency of cleaning and maintenance, and thereby enhances production efficiency.     Clean air is the lifeline of plant tissue culture and pharmaceutical technology development. In plant tissue culture, it is a key technical means to reduce costs and increase propagation coefficients. In pharmaceutical development, it is the legal baseline for compliant production and safeguarding human health. With technological advancements, the shift from traditional static disinfection to dynamic, real-time, human-machine interactive intelligent air purification solutions has become a common trend for improving competitiveness in both industries.

Particulate pollutants in the air are composed of solid or liquid microparticles. The particle size distribution of these particles varies widely, ranging from 0.01 μm to several hundred micrometers. Particles larger than 10 μm, being heavier, gradually settle to the ground under the influence of gravity after a period of random Brownian motion, whereas particles smaller than 10 μm, being lighter, easily float with air currents and are difficult to settle to the ground. It is estimated that over 90% of suspended particles in outdoor air have a particle size of less than 0.5 μm, accounting for less than 1% of the mass; particles larger than 1 μm account for less than 2% of the quantity but make up 97% of the mass. Suspended particles in the air can be classified according to their activity as inert biological particles and biological particles. Non-biological particles are generated from the fragmentation, evaporation, combustion, or aggregation of solid or liquid matter. Biological particles mainly include bacteria, viruses, pollen, flower fluff, and down, and they represent a small proportion of suspended particles.       I. HVAC Air Filtration Classification Air filtration is carried out at multiple locations within HVAC systems to ensure the required air cleanliness for the protection of production processes, users, and air handling equipment and ductwork. In HVAC systems, air filtration is generally divided into three stages: pre-filtration, intermediate filtration, and final filtration, achieved through different types of air filters. Pre-filtration and intermediate filtration (primary and secondary filtration) are typically located at the points where outside air and recirculated air enter the air handling units. Filters should reach a certain efficiency to keep internal equipment (coils, fans) and air handling units relatively clean over an extended period, achieving the expected performance. Final filtration (tertiary filtration) is installed at the discharge section of the air handling unit or downstream (after airflow adjustment) to maintain duct cleanliness, extend the service life of terminal filters (if present), and protect personnel and workspaces from the hazards of suspended particles conveyed by the air handling unit when terminal filters are absent. Terminal filtration devices installed around rooms, such as on ceilings or walls, can ensure the supply of the cleanest air, used to dilute or remove particles released within the room. The cleanliness of air leaving the filter depends on the filter structure and is related to the quantity and quality of the upstream air. Through proper design and correct configuration of air filters, the air quality and conditions required in pharmaceutical workshops can be achieved.   II. Working Principle of Air Filters     When air flows through a series of interconnected pore spaces forming a convoluted path within the microstructure of the filter (such as fibers or membranes), particles are captured in the filter media. The mechanisms by which filter media purifies air include interception, inertial effects, diffusion, electrostatic attraction, sieving, and gravitational deposition. The effectiveness of each mechanism in capturing particles primarily depends on particle size, air velocity, and the specifications of the filter structure (such as fiber diameter). Interception effect: When a particle of a certain size moves close to the surface of a fiber, if the distance from the particle center to the fiber surface is smaller than the particle radius, the dust particle will be intercepted by the filter fiber and deposited. Inertial effect: When the particle mass is large or the velocity is high, particles collide with the fiber surface due to inertia and are deposited. Diffusion effect: Small particles exhibit strong Brownian motion, making them more likely to collide with the fiber surface. Electrostatic effect: Fibers or particles may carry charges, creating an electrostatic attraction that draws particles to the fiber surface. Sieving effect: When the particle diameter is larger than the cross-sectional space between two fibers, the particle cannot pass through and is deposited. Gravitational effect: As particles pass through the fiber layer, they settle on the fibers due to gravity.   III. Filter Applications The following provides an overview of primary to tertiary filtration and terminal filtration parameters.     A. Primary Filtration (Pre-filter) Primary filtration has the lowest efficiency (and also the lowest cost) and is used for pre-filtration, capturing larger particles (diameter above 3 μm, such as insects or plant debris) frequently present in the external air. It also serves as a pre-filter to extend the life of secondary filtration units. It is recommended to use a G4 filter. B. Secondary Filtration (Intermediate Filter) This filter has a higher cost and is generally installed downstream of the primary filter to capture smaller particles (above 0.3 μm) in order to protect coil and fan units, ducts, and personnel in the air handling system. It is recommended to use an F7/8 filter. C. Tertiary Filtration (Final Filter) This type of filter is installed at the discharge section of the air handling unit, downstream of the primary and secondary filters as well as the fan/coil, and can use high-efficiency or HEPA filters. High-efficiency filters: They can capture released mold and other substances (which may grow or accumulate on the condensate (wet) cooling coils) as well as dust on belts and similar surfaces. These filters prevent these substances from moving in the ducts and coming into contact with personnel. It is recommended to use F7/8 filters. HEPA filters: Used when the conditioned space requires a cleanliness level of Class C (100,000), and no terminal filter is used; or to protect terminal filters and extend the service life of downstream HEPA filters. These filters should be equipped with seamless sealing gaskets or silicone seals on the downstream side to create a positive seal, preventing air from bypassing around the filter. Permanent upstream and downstream protective screens should be considered to prevent physical damage to the filter media. Each HEPA filter should be replaceable without interrupting the operation of adjacent filters. H12 (99.5%) to H14 (99.995%, MPPS) filters are recommended. D. Terminal Filtration Structure HEPA filters are generally used as terminal filters in cases where the cleanliness level is above Class 100,000 or when particles generated in the duct may contaminate the supply air. Terminal filters can also be used for recirculated/exhaust air. These filters should have silicone seals on the downstream side to ensure a positive seal, preventing air from bypassing the filter edges. Permanent downstream protective screens (media protection devices) should be installed to prevent physical damage to the filter media. Each HEPA filter in the filter bank should be replaceable without disrupting the operation of adjacent filters. H13 (99.95%) to H14 (99.995%, MPPS) filters are recommended. High-efficiency air diffusers can serve as terminal filtration units and be directly installed in the cleanroom suspended ceiling, suitable for various cleanliness levels and maintenance structures. The main features include: 1. The diffuser housing is made of high-quality cold-rolled steel plate with an electrostatic plastic coated surface; 2. Ensures the airflow velocity for injection, preventing turbulence; 3. Strong versatility, simple construction, and low investment; 4. Compact structure with reliable sealing performance; air inlet can be from the side or top, and flanges are available in square or round shapes. High-efficiency air diffusers are aesthetically pleasing, low in investment, have a simple box structure, and allow easy replacement of HEPA filters, making them the best choice for terminal purification equipment in cleanrooms. Laminar flow hood is an air purification device that provides a localized high clean environment. It is mainly composed of a box, a fan, a primary air filter, a damping layer, a lamp, etc., and the shell is sprayed. The product can be both suspended and ground supported, compact and easy to use. It can be used as a single or with multiple connections to form a strip of clean area. There are two types of clean laminar flow hoods: inside the fan and external fan, and there are two installation methods: suspended type and floor bracket type. The clean laminar flow hood is to pass the air through the fan through a certain air pressure through the high-efficiency air filter, and then the damping layer equalizes the pressure to send the clean air into the working area in a vertical laminar flow type of airflow, so as to ensure that the working area achieves the high cleanliness required by the process. Compared with clean rooms, clean laminar flow hoods have the advantages of low investment, quick results, low requirements for plant civil construction, easy installation, and power saving. Bag-in-bag-out filters are filter housings that use one side to capture hazardous or toxic, biological, radioactive, cytotoxin, or carcinogenic substances. Prevents hazardous airborne substances from escaping from exhaust or return ducts. It is generally located around the room (near the floor) where the material is generated, but it can also be located in the middle. The biggest feature of the bag in and out filter is that the installation, replacement, and detection of the filter are all carried out under the protection of PVC bags (or high-temperature bags), and the filter unit is completely free of contact with the outside air, thus ensuring the safety of personnel and the environment, making the replacement process convenient and fast. To be precise, it is a modular end-air supply unit with self-powered and filtration effect.   FFU (fan filter unit) is divided into two types in shape, one is cuboid and the upper part is slope-shaped; The upper part of the FFU (fan filter unit) is sloped and acts as a diversion, which is conducive to the flow and even distribution of airflow. Rectangular FFU (fan filter unit) generally rely on a different way to equalize the airflow. Structurally, it is divided into two types, one is the whole and the other is split. FFU (fan filter unit) is widely used in the following situations:   1. Insufficient space for the ceiling of the clean room: In some occasions with high cleanliness requirements, the air supply static pressure box on the upper part of the ceiling of the clean room has a great role to balance the pressure on the cross-section of the clean room, but when the FFU (fan filter unit) is used, the ceiling of the clean room is divided into several modules, which can meet the pressure balance requirements of the air supply static pressure box on the upper part of the ceiling by adjusting each module (i.e., FFU (fan filter unit)), thus greatly reducing the height requirements of the static pressure box. In some retrofit projects, FFU (fan filter unit) effectively solves this problem when it is limited by floor height. 2. Insufficient static pressure in the clean room: In some renovation projects, due to the constraints of conditions, the air supply resistance is very large, and it is difficult to overcome the difficulty by relying on the air supply pressure of the air conditioning unit alone, which can be well solved due to the power of the FFU (fan filter unit). 3. Insufficient area of the air-conditioning room: In some renovation projects, due to the small area of the air-conditioning room, it is impossible to accommodate large air-conditioning units.This advantage is also applied to some situations with lower cleanliness requirements.

In recent years, with the rapid development of the new energy electric vehicle industry, lithium batteries, as the core power source, have seen continuously increasing production demand, which in turn has driven the large-scale expansion of battery manufacturing enterprises and significantly heightened the demand for high-standard lithium battery cleanroom construction. An in-depth analysis of the key technical points in the construction of new energy lithium battery cleanrooms:     01 Division of Clean Areas in Lithium Battery CleanroomsCleanrooms are usually divided into different grade areas according to cleanliness requirements to achieve precise control over airborne particles, microorganisms, and other contaminants.Clean Area: This area has the strictest requirements for air quality, particle concentration, and microbial count. High-efficiency air filters (HEPA or ULPA) must be used, positive pressure (or negative pressure under specific process requirements) must be maintained, and personnel are required to wear protective clothing such as cleanroom suits.Semi-Clean Area: The cleanliness standard is slightly lower than that of the clean area but still requires effective control of airborne particles and microorganisms. Generally, high-efficiency air filtration systems are installed and personnel are required to wear cleanroom suits.Partially Clean Area: The control over particle counts is relatively relaxed but still needs to remain within the acceptable range for the process. Standard air filters with basic cleanroom attire are usually sufficient.Non-Clean Area: The cleanliness requirements are the lowest, with no special air filtration equipment or professional cleanroom clothing needed. This area is mainly used for auxiliary or non-critical work areas.     02. Lithium Battery Cleanroom Air Conditioning Treatment SystemTo ensure the stability and cleanliness of the production environment, the cleanroom must be equipped with a comprehensive air treatment system, including air purification devices, supply and return air equipment, and temperature and humidity control systems. Among them, air purification equipment generally uses High-Efficiency (HEPA) or Ultra-Low Penetration Air (ULPA) filters, which can efficiently remove airborne particles, microorganisms, and harmful gases; the fans and air conditioning systems work in coordination to ensure that the temperature, humidity, and airflow organization in the cleanroom always remain at the optimal state required by the process.   03 Interior Installation of Lithium Battery CleanroomsThe interior finishing materials of cleanrooms need to balance functionality with cleanliness maintenance requirements, focusing on ease of cleaning, anti-static performance, and corrosion resistance.Flooring Materials: Common choices include conductive floors, anti-static epoxy floors, or high-durability anti-static PVC floors, which can effectively dissipate static electricity and facilitate routine cleaning.Wall Materials: It is recommended to use stainless steel panels, acid- and alkali-resistant coatings, or other corrosion-resistant, smooth, seamless finishing materials to minimize dust accumulation in corners.Special Function Areas: High-temperature rooms are usually independently isolated, with enclosures made of rock wool sandwich panels and doors equipped with fireproof doors. Low-humidity areas use rock wool partition walls and glass magnesium rock wool ceilings, paired with sealed molded doors and double-layer vacuum glass windows to enhance sealing and thermal insulation performance.   04 Lithium Battery Cleanroom Lighting System Lighting design should take into account functionality, cleanliness, and energy efficiency:The workshop should provide a uniform and bright lighting environment to avoid shadows that may interfere with precision operations;Lighting fixtures must be designed to be dust-free, with smooth surfaces and no seams, to prevent dust adhesion and accumulation;High-energy-efficiency LED fixtures should be preferred, significantly reducing energy consumption and operation and maintenance costs while ensuring adequate illumination.     05 Personnel Movement and Protective Measures in Lithium Battery CleanroomsPersonnel are one of the main sources of contamination in cleanrooms; therefore, it is essential to scientifically plan pedestrian flow channels and implement strict access management and behavioral standards:Establish reasonable changing rooms, air showers, and buffer zones to achieve effective separation of personnel flow and material flow;All personnel entering the clean area must receive professional training to master cleanroom behavioral guidelines, protective equipment wearing standards, and emergency response procedures;Through institutionalized management and regular assessments, continuously enhance employees' awareness of cleanliness and operational proficiency, ensuring the cleanliness and stability of the production environment from the source.

Stepping into a modern food factory, you will encounter a technologically advanced 'mysterious passage'—it resembles a small metal chamber, and before employees or materials enter the clean area, they must 'check in' to pass through it. This is the first crucial barrier safeguarding food safety: the air Shower ! It is not a scene from a science fiction movie, but an indispensable 'air guardian' in the clean workshop of food factories. Today, let us unveil its mysteries and understand how it silently protects the purity and safety of every bite of your food.     1.What is an Air shower ? An air Shower is a mandatory purification device installed between clean areas and non-clean areas. It uses high-speed, clean air streams to conduct comprehensive, all-around, and dead-angle-free blowing on personnel and material surfaces entering the clean area, effectively removing contaminants such as dust, hair, skin flakes, and microorganisms attached to clothing, shoe soles, tools, and packaging materials. In simple terms, it functions as a 'security gate' for cleanrooms, ensuring 'dust-free' passage.   2. Why must food factories be equipped with Air shower? Strictly Adhere to Food Safety Boundaries: Food production requires extremely high standards of hygiene. The human body is one of the largest sources of contamination (carrying large amounts of microorganisms, skin flakes, and fibers). Air Shower can effectively prevent external contaminants from entering clean areas with personnel, reducing the risk of food being contaminated by microorganisms at the source. This is a core requirement of food safety systems such as HACCP and GMP.Ensure Product Quality Stability: Dust and foreign matter not only affect food safety but also compromise the taste and color of products, potentially leading to product waste. Air shower ensure the cleanliness of the production environment, safeguarding the production of high-quality and highly consistent products.Maintain Cleanroom Levels: Cleanrooms (e.g., Class 10,000 or 100,000) require continuous maintenance of specific air cleanliness levels. As an “airlock,” air Shower effectively prevent external dirty air from directly entering, protect the positive pressure environment of the cleanroom, reduce the load on the air conditioning system, and extend the life of high-efficiency filters.Enhance Corporate Professional Image: Advanced purification equipment is a hallmark of modern food factories. Equipping and properly using air Shower demonstrates to clients, partners, and regulatory authorities the company's high regard for food safety and quality management as well as its professional attitude.   3. How does an Air shower work? Preparation for Entry: Employees, after putting on clean garments, caps, masks, and shoe covers in the changing room, carry the materials (which must comply with regulations) and get ready to enter the air shower. Sensor Activation: Upon stepping into the air shower room, the door automatically closes and locks to prevent air exchange between inside and outside. Powerful Purification: The system automatically starts, and the high-efficiency filters (HEPA) on the top and side walls deliver strictly filtered clean air, forming a high-speed, multi-angle "air waterfall." 360° Comprehensive Air Blowing: Air outlets are scientifically distributed to ensure airflow covers the entire body and the surface of the materials, continuously blowing for 10–30 seconds (adjustable), removing attached particles. Removal of Contaminants: The dislodged dust and particles are drawn away through the floor grates or the return air ducts of the air shower room, filtered, and not recirculated indoors. Safe Passage: After the air shower procedure ends, the door to the clean area automatically unlocks, allowing personnel to enter.   4. Friendly Reminder: Instructions for Using the Air Shower     Before entering: Be sure to wear clean and proper clothing, hat, mask, and shoe covers in the changing room, and organize your personal belongings. When entering: The number of people entering at one time should not exceed the limit (usually 1-2 people) to avoid crowding that may affect the performance of the air shower. During the air shower: Remain standing, turn as instructed, and do not touch the nozzles with your hands to avoid damaging the equipment or affecting the airflow. After the air shower: Wait until the door is fully open before exiting. After entering the clean area, please remain quiet and avoid vigorous activities. Maintenance: Regularly clean the interior of the air shower, replace the high-efficiency filters, and ensure the equipment is always in optimal working condition.

Since cleanroom facilities are designed with different levels of requirements depending on their usage, and some work environments require even higher cleanliness standards, FFU（Fan Filter Units） have thus been introduced. The emergence of FFU（Fan Filter Units） has effectively addressed this issue.Using FFU（Fan Filter Units） can effectively solve the problems present in cleanroom projects. The main points are as follows:       1.Space saving — Using FFU（Fan Filter Units）can save space and address the issue of limited maintenance space above the cleanroom ceiling.  High-standard cleanrooms often require Class 100 or even Class 10 laminar hoods to meet process requirements. In such cases, large supply air plenum boxes are installed above the cleanroom ceiling, with fans inside. These plenum boxes, along with supply and return air ducts, occupy significant space, reducing maintenance access and sometimes even affecting the use of fire escape routes.     When FFUs are used, the cleanroom ceiling can be divided into multiple modules, with each module being an FFU. By adjusting each module, the pressure balance requirements of the supply air plenum above the ceiling can be met, significantly reducing the height requirements of the plenum. Additionally, the need for large supply and return ducts can be eliminated, saving installation space. FFUs are particularly effective in renovation projects where ceiling height is limited. Moreover, FFUs come in various sizes and can be customized according to the actual dimensions of the cleanroom. Because of this, they occupy less vertical space within the supply air plenum, and essentially do not occupy space within the cleanroom itself, thereby further maximizing space savings.   2. FFU Flexibility—By utilizing the structural features of the FFU's independence, adjustments can be made at any time, compensating for the limited maneuverability of the cleanroom and thereby addressing the disadvantage of production processes that are not easily adjustable.  The maintenance structure of cleanroom facilities is generally made of metal panels, and once constructed, the layout cannot be freely altered. However, due to continuous updates in production processes, the original cleanroom layout may no longer meet the requirements of new processes, leading to frequent modifications in the cleanroom for product upgrades, which results in significant financial and material waste.By adjusting the number of FFUs, the cleanroom layout can be locally modified to accommodate process changes. Moreover, FFUs come with built-in power, air outlets, and lighting, which can save a substantial amount of investment. Achieving the same effect is nearly impossible for conventional integrated air supply purification systems.Because FFUs are self-powered, they are not limited by specific areas. In a large cleanroom, zoning control can be implemented as needed. Additionally, as semiconductor production processes evolve, the facility layout inevitably requires corresponding adjustments. The flexibility of FFUs makes such adjustments easy without necessitating additional investment.   3. Reducing Operational Burden — The FFU system is energy-saving, thereby addressing the drawbacks of central air supply, such as large air conditioning rooms and increased operating costs of air handling units. If individual cleanrooms within a large-area cleanroom facility require a higher level of cleanliness, the air volume of a centrally supplied air conditioning unit must be large and the fan pressure high to overcome the resistance of ducts as well as the resistance of primary, medium, and high-efficiency filters, in order to meet the requirements. Moreover, in a central air supply system, any failure of an air conditioning unit will cause all cleanrooms associated with that unit to cease operation.Although the initial investment for using FFUs is higher than that for ducted ventilation, the system demonstrates outstanding energy-saving and maintenance-free characteristics during later operation, making FFUs more popular.

The core functions and detailed differences between air shower and pass box in cleanrooms: The core commonality of both is to control contamination and maintain the cleanroom environment level. Both must comply with regulations and standards such as GMP and ISO 14644. However, there are significant differences in their applicable objects, working principles, and operating requirements, as detailed below:      I. Similarities  1. Structural Anti-Cross-Contamination Both are equipped with a double-door interlocking device, preventing both doors from opening simultaneously. This physically blocks the direct airflow between the cleanroom and non-cleanroom (or different levels of cleanrooms), preventing cleanroom pressure imbalance and pollutant diffusion.     2. Consistent Regulations and Management Requirements Both must be included in the cleanroom equipment management system, with complete maintenance and calibration records, and subject to regular audits and inspections.Daily cleaning requires the use of lint-free cleanroom wipes to wipe the inner walls, and no miscellaneous items are allowed to be stored inside the equipment to prevent them from becoming new sources of contamination.   3. Similar Maintenance and Calibration Principles Both require regular inspection of the door seal integrity and the operating status of functional components, and timely replacement of aging consumables (such as filters and UV lamps) to ensure that the equipment is always in a compliant operating state.    II. Differences  1. Applicable Objects Air shower are applicable to personnel and large material carriers, such as operators and inspectors entering the cleanroom, as well as stainless steel trolleys and large turnover boxes carrying materials. They can meet the needs of large and bulk material carriers. Pass box are only suitable for small materials, tools, and documents, such as sample bottles, reagent tubes, cleanroom wipes, sterile gloves, and clean versions of batch production records. Personnel or large items are strictly prohibited from passing through.   2. Core Purification Principles The air shower chamber uses high-speed airflow blowing and filtration as its core principle.A fan blows air, filtered by a high-efficiency particulate air (HEPA) filter, through nozzles at a speed of no less than 25 m/s, forcibly removing dust particles and microorganisms attached to personnel clothing fibers and trolley surfaces. The blown-off contaminants are collected through the return air vents and filtered again, forming a circulating purification process. The pass box uses physical isolation and auxiliary disinfection as its core principle. The basic model only achieves spatial isolation through interlocking doors and has no active purification function; models with UV disinfection have a built-in 253.7nm wavelength UV lamp, which, when activated, irradiates for 15-30 minutes, killing bacteria by destroying the DNA structure of microorganisms.There is no airflow blowing function throughout the process, so it does not change the attachment state of particles on the surface of objects.   3. Installation Location and Environmental Requirements The air shower chamber should be installed in the buffer zone at the main entrance for personnel/materials in the clean area, forming a three-level separation between the non-clean area and the clean area (non-clean area → air shower chamber → clean area). The installation area needs to have sufficient space for passage to ensure that the doors can be fully opened. It also needs to be linked to the pressure difference of the clean area; the pressure difference inside the air shower chamber should be slightly lower than the clean area and higher than the non-clean area. The pass box is directly embedded in the partition wall between the clean area and the non-clean area, or between different levels of clean areas. The installation location should be convenient for personnel on both sides to operate. The wall opening size needs to match the specifications of the pass box. No additional pressure difference control is required; it only needs to ensure consistency with the environmental parameters of the surrounding area.   4. Operating Procedure The operating procedure of the air shower chamber is as follows: After personnel or a trolley enters, the outer door closes, and the interlocking device locks the inner door; the infrared sensor triggers the fan to blow air, with a preset blowing time of 15-30 seconds (adjustable according to the cleanroom class); after the blowing is completed, the fan stops, the inner door unlocks, and personnel or the trolley can enter the clean area. Forcibly opening the interlocking doors is prohibited throughout the process. The emergency stop button should only be used in emergency situations. The pass box operates as follows: personnel on the non-clean side open the outer door, place the items inside, and close the outer door to ensure the interlock is activated; if it is a model with UV disinfection, the UV lamp must be turned on and remain on for the set disinfection time before being turned off; personnel on the clean side confirm that the outer door is closed, then open the inner door to retrieve the items, and finally close the inner door. Note that it is prohibited to open either door while the UV lamp is on to prevent UV radiation leakage and potential injury.   5. Maintenance and Calibration Details Daily maintenance of the air shower room includes checking that the fan is running without abnormal noise, the sensing device is sensitive, and the interlock function is working correctly; weekly maintenance includes cleaning the pre-filters, wiping the nozzles, and checking that the door seals are not damaged; monthly maintenance includes checking the integrity of the HEPA filter (PAO leak test) and calibrating the airflow speed to be no less than 25 m/s; every six months, the pre-filters should be replaced and the fan motor should be inspected.   Daily maintenance of the transfer window includes checking that the interlock function is working correctly, the UV lamp indicator light is on (for models with disinfection), and the observation window is free of stains; weekly maintenance includes wiping the internal surfaces with 75% ethanol and checking that the door hinges rotate smoothly; monthly maintenance includes calibrating the UV lamp irradiation intensity (which must reach a bactericidal threshold of ≥70 μW/cm²) and replacing aging seals; quarterly maintenance includes replacing the UV lamp tubes (which typically have a lifespan of 8000 hours).    III. Complementary Functions  The air shower room addresses the active purification of personnel and large material carriers, preventing the entry of large amounts of contaminants into the clean area; the transfer window addresses the sterile isolation and transfer of small items, avoiding disruption of the clean area pressure difference and environmental stability due to frequent door openings. Both are indispensable and together constitute a comprehensive pollution control system for personnel and material entry and exit in the clean area.

The breakthrough in rubber tree tissue culture technology is accelerating the upgrading of modern agriculture. The innovative technology from the Rubber Research Institute of the Chinese Academy of Tropical Agricultural Sciences, through somatic embryogenesis and cutting propagation, has achieved efficient propagation and quality improvement of rubber seedlings, injecting new vitality into the plant tissue culture industry.   However, plant tissue culture requires extremely high demands on the growth environment, necessitating highly clean laboratory conditions to ensure sterile growth. Traditional air purification equipment often fails to meet the stringent requirements for particle and microbial control, leading to increased contamination risks and affecting the survival rate and quality of tissue-cultured seedlings.     Therefore, the upgrading of air purification equipment has become crucial for the development of tissue culture technology.   With 20 years of accumulated experience in air purification technology, KLC, with its innovative technology and professional design, provides comprehensive clean environment support for rubber tree tissue culture technology. Together, they have built an efficient, intelligent, and easy-to-maintain air purification system, providing strong protection for the growth environment of plant tissue culture.      Wide-Area Purification, Ensuring Sterile Growth  KLC's HEPA air filters, with their excellent filtration performance, ensure that the air cleanliness of the tissue culture laboratory reaches ultra-high efficiency standards. Its high-efficiency filtration performance ensures that tissue-cultured seedlings grow under sterile conditions, reducing the risk of contamination. Continuous air purification covers the entire space, achieving seamless purification and providing stable support for all areas of the tissue culture laboratory, ensuring pollution-free operation throughout the tissue culture process and guaranteeing the continuous and stable operation of a large clean area.      Air Shower Protection, Blocking Contamination Invasion  KLC air shower pass-through windows are used for material transfer, ensuring that materials are air-showered before entering the laboratory to remove surface contaminants. This effectively prevents external contaminants from entering the laboratory through materials, protecting the growth environment of tissue-cultured seedlings.      Horizontal Cleanliness, Protecting Sterile Operations  Some plant tissue culture processes require highly clean bench to ensure sterility. KLC horizontal laminar flow bench provide a horizontal clean airflow, ensuring the air cleanliness of the work area. This provides a sterile working environment for operations such as inoculation and cultivation of rubber tree tissue-cultured seedlings.      Laminar Flow Coverage, Precisely Guaranteeing Sterile Space  Plant tissue culture requires extremely high cleanliness in localized operating areas, especially in some high-precision experimental operations. KLC laminar flow hoods, through their precise laminar flow design, provide a highly clean air environment for specific areas. Their vertical or horizontal laminar airflow patterns effectively remove contaminants from localized areas, ensuring sterile conditions in critical operating zones. Whether for inoculation, cultivation, or other sensitive operations, KLC laminar flow hoods provide precise cleanliness assurance for tissue culture growth, facilitating the smooth progress of experimental procedures.     KLC's air purification solutions provide high-quality clean air for plant tissue culture technology and offer strong support for the development of modern agricultural technology. KLC is committed to providing customized air purification solutions for tissue culture laboratories, research institutions, and agricultural enterprises, helping to advance tissue culture technology.

Cleanrooms place stringent requirements on ventilation systems. They must provide sufficient airflow and pressure while precisely controlling temperature and humidity, ensuring consistent air quality. These requirements apply to various airflow patterns and room sizes.   Many production processes mandate cleanroom conditions because cleanrooms, and even ultra-cleanrooms, guarantee the environmental quality of products during rigorous manufacturing. Even minute impurities in the air can adversely affect production processes, leading to high scrap rates. For example, production environments in fields such as optics and lasers, aerospace, biosciences, medical research and treatment, food and pharmaceutical production, and nanotechnology require a near 100% dust-free and bacteria-free air supply.   However, air conditioning and ventilation systems in cleanrooms consume significant amounts of energy due to high air exchange rates, making energy efficiency and cost critical issues. Therefore, in addition to meeting aerodynamic performance requirements, fans must also meet key standards such as compact size, low noise, use cleanroom-compatible materials, proper control capabilities, networking capabilities, and energy-efficient operation.   FFU are designed specifically to address these needs. They effectively improve ventilation in cleanrooms, ensuring the stability of the production environment and product quality.     An FFU is a device that cleverly combines a filtration system with a fan. It features a ceiling-mounted design, is compact and efficient, and requires minimal installation space. The FFU contains pre-filters and high-efficiency filters. Air is drawn in from the top by the fan, finely filtered, and then uniformly delivered at a velocity of 0.45 m/s ± 20%.   FFU play a crucial role in cleanrooms, clean benches, clean production lines, modular cleanrooms, and localized Class 100 environments. These applications span semiconductor, electronics, flat panel display, and disk drive manufacturing, as well as optics, biomedicine, and precision manufacturing—industries with stringent requirements for air pollution control.   The flexibility and ease of use of FFU: The self-powered, modular design of the FFU makes replacement, installation, and relocation simple and easy. Its matching filters are easy to replace, not limited by location, and ideal for the zoned control needs of cleanrooms. FFU can be easily replaced or moved to adapt to different clean environments as needed. Furthermore, FFU can be used to easily create simple clean benches, clean booths, clean pass-through cabinets, and clean storage cabinets to meet various cleanliness requirements. Its ceiling-mounted installation method, especially in large cleanrooms, significantly reduces construction costs.   Negative Pressure Ventilation Technology: The unique negative pressure ventilation design of the FFU fan filter unit allows it to easily achieve high-level cleanliness in various environments. Its self-powered characteristic maintains positive pressure inside the cleanroom, effectively preventing the infiltration of external particles and ensuring a safe and convenient seal.   Quiet Operation: The FFU fan filter unit boasts excellent quiet operation, maintaining low noise even during prolonged use. Its vibration is very low, ensuring smooth stepless speed regulation and uniform airflow distribution, providing stable support for the clean environment.    Cleanroom Air Supply Units    * Rapid Construction: Utilizing FFU technology, there is no need for ductwork fabrication and installation, significantly shortening the construction cycle.   * Reduced Operating Costs: Supplying clean air to cleanrooms with FFU technology is not only economical but also remarkably energy-efficient. Although the initial investment for FFU may be slightly higher than ducted ventilation, their maintenance-free operation over the long term significantly reduces overall operating costs.   * Space Saving: Compared to other systems, FFU systems occupy less floor height within the plenum chamber and take up virtually no space within the cleanroom.   * Wide Applicability: FFU systems can adapt to cleanrooms and microenvironments of varying sizes and cleanliness requirements, providing high-quality clean air. During the construction or renovation of cleanrooms, it not only improves cleanliness but also effectively reduces noise and vibration.   FFU System Applications in Semiconductor Wafer Shops: FFU systems are widely used in cleanrooms requiring ISO 1-4 air purification levels, playing a crucial role, particularly in the vertical laminar flow operations of semiconductor wafer shops. In the technical mezzanine, air is efficiently delivered to the clean production layer via FFU. This airflow then passes through raised floors and waffle slab openings, reaching the clean lower technical mezzanine. Finally, after being processed by DCC (Dry Cooling Coils) in the return air duct, the air returns to the upper technical mezzanine, forming a cycle. This design effectively supports the wafer fabrication workshop's stringent control over the production environment, including temperature, humidity, cleanliness, and vibration damping.   Furthermore, the application of FFU systems in biological laboratories is also significant. When laboratory personnel handle pathogenic microorganisms, experimental materials containing pathogenic microorganisms, or parasites, FFU systems impose special requirements on laboratory design and construction to ensure experimental safety and a pollution-free environment.   Current laboratory purification systems typically consist of multiple parts, including a static pressure layer, a process layer, a process auxiliary layer, and a return air duct. This system primarily relies on FFU to process the air. Its working principle is: the FFU provide the necessary circulation power, mixing fresh air with recirculated air, which is then delivered to the process layer and process auxiliary layer after passing through ultra-high efficiency filters. At the same time, by maintaining a negative pressure state between the static pressure layer and the process layer, the leakage of harmful substances is effectively prevented, ensuring the cleanliness and safety of the laboratory environment.

Air filters are filtration-based air purifiers. The HEPA filter we often hear about stands for High-efficiency Particulate Air Filter.   Let's break down the five core principles of air filtration to help you understand its underlying logic.     1. Interception Effect: The fibers in a filter are intricately arranged. When airborne dust particles come into contact with the surface of the filter fibers, they are directly trapped if the particle is close enough to the filter material. This phenomenon is particularly evident in dense filter materials, such as the three-dimensional mesh structure formed by ultra-fine fibers in meltblown fabric for masks, which can firmly lock viral aerosols within the fiber gaps.   2. Inertial Effect: The complex arrangement of filter fibers in an air filter causes airflow to encounter obstacles and deflect as it passes through the filter material. Dust particles in the air, under the influence of inertial forces, break away from the streamline and collide with the surface of the filter fibers, depositing there. The larger the particle, the greater the inertial force, the greater the likelihood of it being blocked by the filter fibers, and the better the filtration efficiency.   3. Diffusion Effect: The diffusion effect targets ultrafine particles smaller than 0.1 micrometers. Particles smaller than 0.1 micrometers primarily undergo Brownian motion, exhibiting a disordered trajectory, significantly increasing the probability of contact with filter fibers; the smaller the particle, the easier it is to remove.   4. Gravity Effect: When the airflow velocity is lower than the particle settling velocity, larger particles naturally settle under gravity. Flue gas treatment towers in thermal power plants expand the space and reduce the flow velocity, allowing dust to fall into the dust collection hopper like sand settling to the bottom of water. This mechanism is economical and efficient for treating high concentrations of dust, but its effect on suspended particles is limited, and it is usually used as a pretreatment method.   5. Electrostatic Effect: Electrostatic electret technology charges the fibers, giving the filter material the ability to actively capture particles with opposite charges, much like a magnet attracts iron filings. This mechanism is particularly effective for charged particles in PM2.5, and industrial dust removal equipment performs electret treatment on the filter surface.

The production environment for semiconductor devices is extremely sensitive to the presence of contaminants. Even small amounts of gaseous or particulate contaminants can reduce product quality. Therefore, cleanliness requirements in semiconductor device manufacturing are far higher than in other industries.     Throughout the entire chip and semiconductor device manufacturing process, process environment contamination control is crucial. The air cleanliness of core processes needs to meet ISO Class 1 standards, with gaseous molecular contaminant (AMC) concentrations below one part per billion. Substandard process environments can lead to a significant reduction in product yield.   Ordinary air contains a large number of particulate contaminants such as microparticles and dust, as well as gaseous contaminants such as sulfur dioxide, nitrogen oxides, and ammoniaaa. Only after treatment can it enter a cleanroom. Because cleanrooms used for producing semiconductors and other microelectronic devices must maintain standard cleanliness levels 24/7, the cleanroom air conditioning system (including the exhaust system), its associated heat and cold sources, and corresponding delivery systems must operate 24 hours a day, which is significantly different from other conventional air conditioning systems.   As the power source, the fan consumes most of its energy due to the combined resistance of its components. Furthermore, the air filter's resistance accounts for approximately 50% of the fan's total head. Therefore, reducing the energy consumption of air conditioning filters is crucial for lowering building energy consumption and carbon emissions. From the perspective of improving energy efficiency and reducing energy consumption, optimizing air filter performance without compromising filtration requirements is essential.     Filter energy consumption is directly determined by average resistance and is related to initial resistance and dust holding capacity. Reducing initial resistance, increasing dust holding capacity, and minimizing the increase in resistance during dust holding are effective ways to reduce energy consumption, thus lowering energy costs for customers and contributing to environmental protection.

Food safety is paramount. For a responsible food company, having a standard-compliant cleanroom is like donning a "golden armor" for its products.   However, this "armor" isn't a monolithic structure. Instead, it's scientifically divided into different zones based on production processes and hygiene requirements, with layers of protection to precisely filter risks.      Core Principle: Why Zoning is Essential?    The core purpose of cleanroom zoning is singular: to control contamination and prevent cross-contamination.   Contamination sources mainly come from three aspects: people, machines, materials, methods, and environment. By physically isolating areas with different cleanliness requirements and coordinating different pressure differentials, airflow organization, and personnel purification procedures, a unidirectional contamination control gradient can be formed from low-cleanliness to high-cleanliness areas, ensuring a high level of cleanliness in the core production areas.    Four Core Functional Areas of a Cleanroom    Typically, a standard food cleanroom is divided into the following four main areas from the inside out, with cleanliness requirements decreasing sequentially.   1. Core Production Area (Clean Zone)   Function: This is the area where products are directly exposed to the environment, including processes such as ingredient preparation, mixing, filling, inner packaging, cooling, final cooling of semi-finished products for perishable foods, and temporary storage after disinfection of inner packaging materials. This is the "heart" area with the highest hygiene requirements.   Cleanliness Level: Typically requires Class 10,000 or higher. For certain special foods, some processes even require localized purification down to Class 100.   Management Requirements: Personnel must undergo the strictest first and second changing procedures before entering. Materials are introduced through a pass-through window after disinfection. This area maintains positive pressure to prevent backflow of air from lower-level areas.   2. Semi-Clean Area (Buffer Zone)   Function: This is the "buffer zone" before entering the clean area, a purification preparation area for personnel and materials before entering the core area. It mainly includes: changing rooms, air showers, handwashing and disinfection rooms, material buffer rooms, and equipment cleaning and disinfection rooms.   Cleanliness Level: Cleanliness requirements are lower than the core area but higher than general areas, typically Class 100,000 or Class 300,000.   Management Requirements: In this area, personnel complete key steps such as changing shoes, putting on cleanroom garments, and washing and disinfecting hands. Materials undergo pre-treatment here, including removing outer packaging and wiping and disinfecting surfaces. This area serves as a crucial "filter."   3. General Work Area (Non-Clean Area)   Function: Areas where products are not directly exposed or only undergo simple primary processing. Examples include: raw material warehouses, outer packaging areas, finished product warehouses, testing laboratories (partial), equipment maintenance rooms, and office areas.   Cleanliness Level: No strict air cleanliness requirements, but good environmental hygiene must still be maintained, complying with basic food factory hygiene standards (e.g., GB 14881).   Management Requirements: Personnel do not need to undergo complex changing procedures, but must wear work clothes and maintain personal hygiene. Access control must be installed between this area and the semi-clean area for physical isolation.   4. Auxiliary Area   Function: Areas that provide power and support to the cleanroom. Although not directly involved in production, they are crucial. Includes: air conditioning room, water treatment system, changing rooms, restrooms, and sanitary ware rooms.   Management Requirements: These areas require regular maintenance to ensure stable operation. Restrooms and sanitary ware rooms, in particular, must be strictly managed; their doors must never open directly towards the clean area.    Dynamic Defense Line: Intelligent Design of Personnel and Material Flow    Static zoning alone is insufficient; dynamic personnel and material flow route design is the soul of zoning.   Personnel Flow Route: Must follow the unidirectional flow principle of "low clean area → high clean area".   Correct Route: General Area → Shoe Change → First Changing Room (Removing Outerwear) → Second Changing Room (Putting on Cleanroom Gown, Handwashing and Disinfecting) → Air Shower → Core Clean Area.   Absolutely Prohibited: When returning from a high clean area to a low clean area, the same route must not be used; a dedicated passage must be designed to avoid cross-contamination.   Material Flow Route: Raw Materials → Unpacking and Preliminary Processing (General Area) → Through Material Transfer Window (after Disinfection/Wiping) → Buffer Room → Core Clean Area.   Finished Products flow out in the opposite direction, but separately from the raw material flow to avoid cross-contamination.   The zoned management of cleanrooms in food factories is a comprehensive art that integrates architecture, aerodynamics, microbiology, and food processing. Every wall, every pass-through window, and every air shower represents a solemn commitment to food safety for consumers.   Understanding this knowledge not only helps food industry professionals better implement regulations but also gives every consumer greater peace of mind and confidence in the food we consume. Because true deliciousness stems from the utmost respect and protection for detail.