Blog

In air conditioning systems for high-purity environments such as cleanrooms, fan-filter units (FFU) are one of the core devices for achieving air cleanliness control. Through their efficient air filtration and stable airflow distribution, FFU ensure the purity and uniform distribution of indoor air. They work collaboratively with dry coil units (DC) and other components to maintain cleanroom environmental conditions.      High-Efficiency Air Filtration and Airflow Distribution  FFU, with their built-in HEPA filters, remove airborne particles, including dust, bacteria, and viruses, ensuring that the air delivered to the cleanroom meets high cleanliness standards.   FFU also utilize their built-in fans to create stable vertical laminar or turbulent airflow, preventing localized contamination. This stable airflow is crucial for maintaining cleanroom cleanliness, especially in the semiconductor manufacturing and biopharmaceutical industries, where cleanliness requirements are extremely high.    Cooperation and Application Scenarios  In dry coil systems, FFU work collaboratively with dry coil units (DC) and other components, such as the main air handling units (MAU). The MAU is responsible for introducing and processing outdoor fresh air, removing particulate matter through primary and secondary filtration, and conditioning the fresh air to the specified temperature and humidity.   The fresh air treated by the MAU is mixed with a portion of the return air, filtered by the FFU, and then delivered to the cleanroom. The indoor air is cooled or heated by the dry coil before being recirculated to the return air duct and mixed with the fresh air, forming a closed-loop air circulation system.   The FFU operates continuously to maintain air circulation frequency and ensure indoor air cleanliness. The dry coil adjusts the chilled water flow or temperature based on temperature sensors, handling only the sensible heat load and avoiding interference with temperature and humidity control. This clear division of labor improves overall system performance and reliability.   Among the many FFU products available, the KLC FFU is an excellent choice on the market for its superior performance and flexible design. Utilizing KLC's proprietary high-efficiency filters, the KLC FFU achieves highly efficient air filtration, ensuring high indoor air cleanliness.     Its compact design makes it easy to install and maintain, while also offering low noise levels and high energy efficiency, meeting the requirements of various cleanliness levels. The KLC FFU also offers flexible installation options and intelligent control options, enabling single-unit manual control or group monitoring of multiple units, adapting to cleanroom applications ranging from small to large-scale.   The KLC FFU has demonstrated outstanding performance in practical applications, particularly in fields such as semiconductor manufacturing, biopharmaceuticals, and precision electronic assembly, providing users with efficient and reliable air purification solutions. Its efficient filtration performance and stable airflow distribution effectively prevent condensation from contaminating wafers, ensuring a sterile environment in pharmaceutical production while also safeguarding the accuracy and stability of the equipment.   The KLC FFU's low noise operation and energy-efficient design also excel in cleanrooms with stringent environmental requirements, making it an ideal air filtration option.   As the core air filtration device in dry coil systems, the FFU provides a reliable solution for high-purity environments such as cleanrooms through its efficient filtration capacity and stable airflow distribution. Its synergistic operation with the dry coil and other components further optimizes system performance and reliability.   In fields such as semiconductor manufacturing, biopharmaceuticals, and precision electronic assembly, the FFU has become a critical piece of equipment for maintaining high-purity environments, ensuring efficient and stable production processes.

In modern industrial production, cleanliness is a critical factor in many industries, such as food processing, electronics manufacturing, and biomedicine. To ensure a clean and sterile production environment, air showers have emerged as an efficient and essential device. They serve not only as a physical barrier but also as an invisible guardian, ensuring product quality and safety.    Necessity and Importance  Air showers are the essential gateway between non-clean areas and clean areas. Their importance lies in their ability to effectively reduce dust, particles, and bacteria introduced by people and goods entering and exiting the cleanroom, thereby maintaining high cleanliness levels within the cleanroom. This equipment uses high-pressure clean airflow to fully drench the human body, rapidly removing attached contaminants and providing a solid defense for the cleanroom.    Multiple Functions and Intelligent Applications  Air showers are more than just simple showering equipment; they incorporate a variety of intelligent features. For example, smart air showers provide voice prompts to guide users through the showering process, improving efficiency while ensuring a thorough cleansing experience. Furthermore, the front and rear doors of the air shower room feature electronic interlocking, preventing the ingress of unpurified air and further enhancing its function as an "airlock." In terms of automated control, modern air showers generally utilize PLC intelligent control. LED displays provide real-time information on the air shower's operating status, the interlocking status of the two doors, and the progress of the shower cycle, providing operators with clear and intuitive feedback. Furthermore, the introduction of infrared sensing automatic showering technology makes the air shower process more intelligent and user-friendly, reducing manual operation while improving showering accuracy and efficiency.      Wide Application and Scenario Adaptability  Due to its wide applicability and flexibility, it has been widely used across various industries. In the food industry, it helps reduce cross-contamination within production workshops and ensure product hygiene quality. In electronics manufacturing, it effectively prevents dust from affecting precision equipment, improving product yield and reliability. In the biopharmaceutical industry, it is a critical device for maintaining a sterile environment and preventing microbial contamination. Furthermore, various types and specifications have been developed to meet the needs of different industries and scenarios, such as single-person single-blow air showers, multi-person double-blow air showers, and corner air showers, to meet the needs of different occasions. Furthermore, a variety of materials are available, including stainless steel, steel plates, and color-coated steel plates, to meet the corrosion resistance and aesthetic requirements of different environments.

In hospital clean areas, you might often see gleaming stainless steel Pass Box. While seemingly ordinary, they're actually "invisible guardians" of infection control.    1. Rust-Free = Safer  Ordinary Pass Box can rust and peel over time, becoming a breeding ground for bacteria. Stainless steel, on the other hand, is corrosion-resistant and easy to disinfect. For example, while hydrogen peroxide fumigation is commonly used in operating rooms, ordinary materials might corrode, but stainless steel Pass Box can withstand it.    2. Sealing Comparable to a Safe  Pass Box used in hospitals must be "leak-proof." For example, when chemotherapy drugs are delivered in a pharmacy, a loose seal could allow toxic particles to escape. High-quality stainless steel Pass Box feature an airtight design, preventing even air from escaping.      3. Unexpected Function: Labor Savings  Hospitals have calculated that traditional Pass Box require frequent manual disinfection, while stainless steel Pass Box with self-cleaning features (such as UV light and high-efficiency filtration) save over 200 man-hours annually.    Conclusion:  Do you think hospitals are just obsessed with appearance? In fact, every design is a race against microorganisms.  

We are thrilled to announce that KLC will be at CLEANFACT & RHVAC VIETNAM 2025! This is the premier event for the cleaning, sanitation, and HVAC-R industries in Vietnam, and we can't wait to be a part of it.    BOOTH No:  A43 11–13 September 2025   Join us to: Explore our latest innovations in air filtration. Engage in insightful discussions on the future of clean air technology.   Connect with our experts and discover solutions for your needs. Let's collaborate to shape a healthier, cleaner future. We look forward to seeing you there!  

In chip manufacturing plants, even a speck of dust as small as 0.1 microns can render an entire wafer scrapped; in sterile operating rooms, bacterial intrusion directly threatens surgical safety. In these environments, where cleanliness is crucial, HEPA filters serve as the "last line of defense" protecting the air.   KLC As an industry service provider with years of experience in air purification, we'll break down the technical secrets of HEPA filters and how they create a clean barrier for various industries.    Basic Principles of HEPA Filters    1. Physical Interception: Micron-Scale "Air Screening"   Using ultrafine glass fibers or composite filter media, nanometer-scale pores (over 1,000 times smaller than the diameter of a human hair) are formed between the fibers, acting like a precision sieve that directly intercepts particles larger than these pores. The Shangjing HEPA filter utilizes a gradient pore design, achieving a 99.9% interception rate for particles larger than 5μm.   2. Inertial Collision: Traps Particles   When airflow suddenly changes direction while passing through filter media fibers, larger particles (0.5-10μm) are deflected by inertia and directly collide with and adhere to the fibers. This principle is particularly critical in the high-speed airflow systems of semiconductor plants, quickly capturing fine debris generated by metal processing.     3. Diffusion Effect: A "Brownian Motion Trap" for Nanoparticles   Viruses and nanoaerosols smaller than 0.1μm experience random motion due to molecular thermal motion, increasing the probability of contact with the filter media. Our electrostatically charged filter media technology improves diffusion efficiency by 30%, achieving a 99.99% filtration efficiency for the novel coronavirus (approximately 0.1μm).   4. Electrostatic Adsorption: Giving the Filter Media a "Magnetic Coat"   The electret treatment imparts static electricity to the filter media. The charged fibers can attract particles of opposite charge, even polarizing neutral particles. In PM2.5 control scenarios, this technology can increase the filtration efficiency of submicron particles to over 99.97%.    Its Function and Role in Cleanrooms    Stability Does Not Require Compromise   1. Providing Ultimate Air Purification High-efficiency filters effectively remove tiny particles, bacteria, viruses, and other harmful substances from the air, ensuring that the air cleanliness within the cleanroom meets predetermined standards. In chip manufacturing workshops in the electronics and semiconductor industry, air cleanliness requirements are extremely high. Even the smallest dust particles can cause chip defects and affect product quality.     High-efficiency filters effectively remove airborne particles 0.3μm or smaller, typically achieving a filtration efficiency of over 99.97% for particles as small as 0.3μm. Some ultra-high-efficiency filters even achieve filtration efficiencies as high as 99.9995%, providing a nearly dust-free clean air environment for chip manufacturing and meeting the stringent air quality requirements of the production process.   2. Maintaining a Stable Clean Environment High-efficiency filters operate continuously and stably, providing uninterrupted, highly efficient filtration of air entering the cleanroom, thereby reducing the accumulation and spread of particulate matter within the cleanroom. They not only prevent the intrusion of external contaminants but also rapidly remove pollutants generated by human activity and production processes, helping to maintain a stable cleanliness within the cleanroom and achieve a dynamic cleanroom balance.   In medical operating rooms, the movement of personnel and the operation of equipment generate a certain amount of dust and microorganisms. High-efficiency filters continuously filter the air, effectively removing these pollutants and maintaining a high level of cleanliness within the operating room, thereby reducing the risk of surgical infection.   In precision instrument manufacturing workshops, the production process may generate trace amounts of pollutants such as metal debris and dust. High-efficiency filters quickly remove these pollutants, ensuring the air in the workshop remains clean, providing a stable environment for precision instrument manufacturing and safeguarding the accuracy and performance of products.   3. Protecting Downstream Equipment and Products   In cleanrooms, high-efficiency filters are typically installed at the end of the air handling system, providing the final purification step for air entering the cleanroom. This not only ensures the cleanliness of the cleanroom environment but also protects downstream equipment and products from contamination and damage from harmful airborne particulate matter.   In semiconductor manufacturing equipment, key components such as optical lenses and silicon wafers are extremely sensitive to dust. Even the smallest amount of dust particles can cause equipment failure or degrade product quality. High-efficiency filters effectively intercept airborne particulate matter, preventing it from entering the equipment, thus protecting its normal operation and product quality. In aseptic filling plants in the food and beverage industry, high-efficiency filters remove airborne microorganisms and dust, preventing contamination of food and beverage products, extending their shelf life, and safeguarding consumer health.

  From September 11th to 13th, 2025, KLC participated in RHVAC & CLEANFACT 2025 in Vietnam. As a leading brand in China's air purification and cleanroom solutions sector, KLC showcased its cutting-edge high-efficiency filters and innovative cleanroom technologies. With its superior product performance and professional solutions, KLC served as a vital bridge between the Vietnamese and Southeast Asian markets, further strengthening exchanges and cooperation within the cleanroom technology industry.     The Vietnam HVAC & Refrigeration & Cleanroom & High-Tech Factory Facilities Exhibition, which has undergone multiple iterations, has attracted participants from countries including Japan, South Korea, the European Union, Singapore, China, and India, including investors, general contractors, engineers, and representatives from manufacturing, cleanroom, and HVAC/Refrigeration industry associations. Notably, this exhibition was held concurrently with the Vietnam International Industrial Exhibition 2025 (VIET INDUSTRY 2025), which encompassed sectors such as machinery manufacturing, automation, pharmaceutical technology, and the construction industry. Together, they fostered a diverse exhibition ecosystem, strengthened industry collaboration and cooperation in modern infrastructure development, and provided exhibitors, sponsors, and partners with an excellent opportunity to explore business prospects and establish connections within the industry.      Technical Interaction and Exchange    At the booth, KLC's team of technical experts engaged in in-depth and fruitful exchanges with visitors and industry experts from Vietnam, surrounding regions, and around the world. Through product sample dissections, performance demonstrations, and case studies, the KLC team thoroughly addressed specific questions regarding product compatibility, energy-saving optimization, and maintenance cycles.      A Successful Ending: Fruitful Harvest, Looking Forward to the Future    The KLC booth remained bustling with visitors and a lively atmosphere throughout the multi-day exhibition. This RHVAC & CLEANFACT 2025 journey was not only a successful brand showcase and product promotion, but also a platform for profound market insights and industry exchange. KLC will continue to deepen its presence in the Southeast Asian market, continuously increasing R&D investment, launching products that better meet regional needs, and continuously improving its sales and service network. KLC is committed to becoming a "Clean Air Gold Partner" that supports industrial upgrading in Vietnam and Southeast Asia, working with customers to build a clean, healthy, and efficient industrial environment for the future.

In modern industrial and commercial environments, air quality management has become a critical consideration for business operations. Chemical air filters, as a key component of air purification technology, have been used across multiple industries for decades. They effectively remove odors, corrosive gases, and harmful or toxic gases from the air, protecting personnel health and optimizing the production environment.    The Development of Chemical Filtration Technology    Activated carbon, one of the primary materials used in chemical filtration technology, has been used as far back as 3750 BC. Egyptians first used charcoal to smelt ore to create bronze. By 1500 BC, activated carbon's uses had expanded to treating intestinal ailments, absorbing odors, and for papyrus writing. By 400 BC, ancient Indian and Phoenician civilizations had discovered activated carbon's antiseptic properties and used it for water purification.   Today, activated carbon is widely used in air filtration technology. For more detailed information on the classification and filtration mechanisms of chemical filters, please refer to "AMC Pollutant Control - Filter Media."   In addition to activated carbon, chemical filtration materials also include coconut shell activated carbon, ion exchange resins, and other adsorbent media, providing highly effective purification in diverse environments.      Wide Application of Chemical Filters    With the acceleration of industrialization, air pollution, particularly chemical pollution in the industrial sector, has become increasingly prominent. Unlike conventional cleanroom methods for controlling particulate and microbial contamination, the molecular size of chemical pollutants is often too small to be effectively captured by traditional particle filters. Therefore, chemical filtration technology has become essential for air pollution control, with applications across a wide range of industries.      Air Molecular Contamination Control (AMC)  In high-tech industries such as semiconductor, microelectronics, and photovoltaic manufacturing, even the slightest change in air quality can impact product yield. Consequently, these industries place extremely high demands on chemical filters, requiring the removal of acids, alkalinity, volatile organic compounds (VOCs), refractory compounds (RCs), oxidants, dopants, and ozone to ensure a stable production environment.

The Battery Show and Electric & Hybrid Vehicle Technology Expo 2025, a highly anticipated annual event for the global new energy industry, was successfully held in the United States on October 9th. As a leading company in air filtration and cleanroom solutions, KLC participated in the exhibition, showcasing cutting-edge technology, professional solutions, and in-depth industry insights. We worked with global customers and partners to successfully demonstrate our key value in supporting the electric vehicle and battery manufacturing supply chain.   High-precision battery workshop air filters: We showcased HEPA/ULPA high-efficiency filters for controlling the battery production environment. These products effectively remove fine dust and metal particles from the air, ensuring extremely clean battery production, and guaranteeing consistent and safe battery performance from the source, attracting significant attention from battery manufacturers.      Professional Exchanges, Insights into the Industry  The KLC booth was bustling with visitors throughout the exhibition. We engaged in hundreds of high-quality, in-depth discussions with representatives from battery manufacturers, electric vehicle OEMs, component suppliers, and research institutions from North America and around the world.     This exhibition was not only a successful brand showcase, but also a valuable journey of learning and insight. We deeply feel that with the rapid development of the electric vehicle industry and the continuous iteration of battery technology, the requirements for "purity" and "precision control" in the production environment are becoming more stringent than ever before.     KLC will use this exhibition as a new starting point to continuously increase R&D investment and continuously optimize our products and technologies, striving to provide safer, more efficient, and more economical air filtration and cleanroom solutions for the global new energy industry chain. We look forward to transforming the sparks generated during the exhibition into fruitful future collaborations and working with industry colleagues to contribute the "pure power of KLC" to driving the future of green mobility.

The principles, methods, and results of air filtration applications in pharmaceutical and medical device manufacturing systems. In this sector, air filtration is a core element in ensuring product quality, safety, and regulatory compliance, far exceeding the importance of general industrial or residential environments.    Why Use Air Filtration?  In pharmaceutical and medical device manufacturing, the core principle of air filtration systems is strict contamination control. The goal is to create and maintain a controlled environment that meets specific cleanliness levels to prevent product contamination from various airborne sources.    Specific principles and motivations include:    Preventing microbial contamination: This is a critical goal, especially in the production of sterile pharmaceuticals (such as injectables and eye drops) and implantable/sterile medical devices. Airborne microorganisms such as bacteria, fungal spores, and viruses can cause product failure, lead to patient infection, or even be life-threatening if they land on product or contact surfaces. Air filtration (particularly HEPA/ULPA grades) is the primary means of removing airborne microorganisms and their carriers (such as dust particles).   Preventing Particulate Contamination: Non-viable particles in the air, such as dust, fibers, metal shavings, and skin flakes, are also serious contaminants for pharmaceuticals (especially injectables, which can cause blood vessel blockage) and precision medical devices (which can affect performance or trigger foreign body reactions in the body). High-efficiency filtration can keep the number of airborne particles to extremely low levels.   Preventing Cross-Contamination: In workshops producing different types of pharmaceuticals or active ingredients, air filtration helps coordinate airflow design to prevent powder or active ingredients from previous batches from spreading through the air and contaminating subsequent products.      II. How is Air Filtration Implemented?    Air filtration in pharmaceutical and medical device production is a complex and sophisticated systems engineering process, primarily manifesting in the following aspects:    Cleanroom HVAC System:    Core Support: Air filtration functions are primarily integrated into HVAC systems designed specifically for cleanrooms.   Multi-stage Filtration Strategy: Air handling units (AHUs) typically have multiple stages of filtration:   Pre-filter: Typically rated G4/MERV 8/ISO Coarse, removes large particles and protects the medium-efficiency filter.   Medium/High-Medium Filter: Typically rated F7-F9/MERV 13-15/ePM1, ePM2.5, further purifies the air and reduces the burden on the final HEPA filter.   Terminal Filtration: This is the most critical step in ensuring cleanroom quality. These filters are installed at the very end of the air supply system, directly supplying air into the cleanroom.   Filter Type: HEPA (High-Efficiency Particulate Air) filters (H13, H14) or ULPA (Ultra-Low Penetration Air) filters (U15 or higher) are commonly used. The specific cleanliness level to choose depends on the required cleanliness level of the area (for example, an ISO 8/GMP Grade D area might use H13, an ISO 7/GMP Grade C area uses H14, and an ISO 5/GMP Grade A/B core area must use H14 or higher, combined with unidirectional airflow).      Installation Type:    High-efficiency air inlets: HEPA/ULPA filters are installed in a custom-designed air inlet housing, with air delivered through diffusers (often used in areas with non-unidirectional airflow).   Fan filter units (FFUs): Fans and HEPA/ULPA filters are integrated into a modular unit. These units are densely mounted in the ceiling to create vertical, unidirectional (laminar) airflow over a large area. They are the primary method for achieving an ISO 5/GMP Grade A environment.   Airflow pattern: This works closely with filtration to control the direction of air flow to remove contaminants.   Unidirectional Flow (Laminar Flow): In critical operating areas (such as aseptic filling and areas directly exposed to product, corresponding to GMP Grade A), HEPA/ULPA-filtered air flows through the work area in uniform, parallel streams (typically vertically downward) at a specific velocity (e.g., 0.36-0.54 m/s). This quickly "blows away" generated particles and prevents them from settling above the product or on critical surfaces.   Non-Unidirectional Flow (Turbulent Flow): In areas with lower cleanliness requirements (such as GMP Grades C and D), filtered air is introduced through supply vents, mixed with room air to dilute contaminants, and exhausted through return vents. Maintaining cleanliness relies on a sufficiently high air changes per hour (ACH).    Localized Protection & Containment Systems:    Laminar Flow Hoods / Biological Safety Cabinets (BSCs): These provide a small, unidirectional, clean environment to protect products or personnel.   Isolators / Restricted Access Barrier Systems (RABS): These provide highly enclosed physical barriers, maintaining a GMP Grade A environment and separating personnel from the core aseptic processing area. They are a key technology in modern aseptic production, relying on HEPA/ULPA filtration for both internal air circulation and exchange with the external environment.   Exhaust Air Filtration: For operating rooms or equipment generating hazardous dusts (such as highly active pharmaceutical powders), aerosols, or biohazardous materials, exhaust air must be filtered through HEPA filtration (sometimes even two stages of HEPA) before discharge to protect personnel and the environment. A bag-in/bag-out (BIBO) filter replacement system is often used to ensure that operators do not come into contact with contaminated filters when replacing used filters.    III. Application Outcomes (What are the Outcomes?)  The successful application of air filtration systems in the pharmaceutical and medical device sectors is crucial: Major Pros (Pros):   Ensuring Product Safety and Quality: Minimizing the risk of microbial and particulate contamination ensures the safety and effectiveness of finished drugs and medical devices, which is directly related to patient health and life.   Meeting Regulatory Compliance: This is a prerequisite for companies to obtain production licenses and market their products. Compliance with standards such as GMP and ISO 14644 is mandatory. Failure to comply can result in serious consequences such as warning letters, product recalls, production suspension, and even license revocation.   Improving Production Reliability and Consistency: A stable, clean production environment reduces process fluctuations and deviations caused by environmental factors, helping to ensure consistent quality between product batches.   Reduce Batch Rejection Due to Contamination: Effective contamination control significantly reduces the risk of products failing quality inspection due to microbial or particulate contamination, thereby mitigating significant economic losses.   Ensure Operator Safety: Exhaust air filtration and isolation technologies protect employee health in processes handling highly active or toxic substances.   Improve Corporate Reputation and Market Competitiveness: Strict adherence to high-standard production practices is the cornerstone of the credibility of pharmaceutical and medical device companies.    Summary:  Air filtration plays an absolutely core role in pharmaceutical and medical device manufacturing. It is a cornerstone technology for ensuring product sterility and the absence of particulate contamination, thereby safeguarding patient safety and meeting regulatory requirements. Its application is highly systematic and sophisticated, closely integrated with HVAC systems, air flow management, and isolation technologies. While costly and maintenance-intensive, the resulting product safety, regulatory compliance, and production reliability are fundamental to the survival and growth of this industry.

Cleanroom are designed to meet varying cleanroom cleanliness requirements, such as Class 100, Class 1000, Class 10,000, Class 100,000, Class 300,000, and even higher. This is why FFU have emerged as a valuable solution to these challenges.    FFU can effectively address challenges in cleanroom. The key advantages are as follows:    1. Space Savings – FFU can save space and address the limited maintenance access above cleanroom ceilings.   Because high-quality cleanroom require Class 100 or even Class 10 laminar flow hoods to meet process requirements, large supply air plenums are installed above the cleanroom ceilings. These plenums, along with the supply and return air ducts, take up significant space, limiting maintenance access and sometimes even restricting access to fire escapes.   When using FFU, the cleanroom ceiling is divided into several modules, each of which serves as an FFU. This allows for adjustments to meet the pressure balance requirements of the supply air plenum above the ceiling, significantly reducing the required plenum height. This also eliminates the need for large supply and return air ducts, saving installation space. FFU are particularly effective when floor height restrictions are imposed during renovation projects. Furthermore, FFUs are available in a variety of sizes and can be customized to the exact size of the cleanroom. As a result, they occupy less floor height within the supply air plenum, or even virtually no space within the cleanroom, further conserving space.     2. FFU Flexibility – The FFU's independent design allows for immediate adjustments, compensating for the lack of cleanroom flexibility and addressing the inherent limitations of production process adjustments.   Cleanroom structures are typically constructed of metallic panels, and their layout cannot be altered after construction. However, due to constant changes in production processes, the existing cleanroom layout can no longer meet new process requirements. This leads to frequent cleanroom modifications for product upgrades, resulting in significant financial and material waste.   By increasing or decreasing the number of FFU, the cleanroom layout can be locally adjusted to accommodate process changes. Furthermore, FFU have their own power supply, air vents, and lighting, saving significant investment. This is virtually impossible to achieve with conventional centralized air purification systems.   Because FFU are self-powered, they are not restricted by location. Within a large cleanroom, they can be controlled in zones as needed. Furthermore, as semiconductor production processes evolve, the layout inevitably needs to be adjusted accordingly. The flexibility of FFU makes such adjustments easy and eliminates the need for secondary investment.   3. Reduced Operational Burden - FFU systems are energy-efficient, eliminating the drawbacks of centralized air supply systems, which often require bulky air conditioning rooms and high operating costs for air conditioning units.   If individual cleanroom within a larger cleanroom building require a higher cleanliness level, centralized air supply units with high air volumes and fan pressures are required to overcome resistance in the ductwork and the resistance of the primary, medium, and high-efficiency filters to meet the required cleanliness level. Furthermore, a single air conditioner failure in a centralized air supply system would halt operation in all cleanroom served by that unit.   Although the initial investment in FFU is higher than that of ducted ventilation, their outstanding energy-saving and maintenance-free features make FFU more popular.

 What is Cleanroom Engineering?    Simply put, cleanroom engineering is a systematic project that uses air filtration, airflow control, and environmental monitoring to control pollutants such as dust, microorganisms, and harmful gases within specific standards in a cleanroom, while maintaining stable parameters such as temperature, humidity, and pressure differential.   From ISO 14644 cleanliness levels (Class 1 to Class 9) to GMP pharmaceutical workshop standards, the requirements for cleanliness levels vary significantly across industries—the electronics industry may require Class 5 (≤352 0.5μm particles per cubic meter), while food workshops typically only require Class 8.      Why must factories prioritize cleanroom engineering?    1. Maintaining the Bottom Line of Product Quality In precision manufacturing fields such as semiconductors and optical instruments, even particles 1/200th the size of a human hair can cause short circuits and decreased precision; in the biopharmaceutical industry, excessive microbial levels directly violate GMP regulations, posing a risk of production stoppage. 1. Cleanroom engineering controls pollution at its source, reducing product defect rates by over 30%.   2. Compliance is a prerequisite for production. Industries such as pharmaceuticals, medical devices, and food contact materials are subject to mandatory national cleanliness standards for production environments. Even with advanced technology, workshops that fail cleanroom engineering acceptance cannot obtain production licenses.   3. Reduce hidden production costs. Uncleaned workshops may increase costs due to frequent rework, batch scrapping, and accelerated equipment wear. A well-designed cleanroom system, while requiring initial investment, can recoup costs in the long run through stable production efficiency.   4. Protect occupational health. In industries such as chemicals and spray painting, untreated volatile organic compounds (VOCs) and dust in workshops can harm employee health. Cleanroom engineering's waste gas treatment and fresh air systems can simultaneously achieve "clean production" and "healthy work."      What are the core systems included in cleanroom engineering?    A complete cleanroom system is not a single piece of equipment, but the result of multiple systems working together:   Air Purification System: The core components are high-efficiency particulate air (HEPA) filters and ultra-high-efficiency particulate air (ULPA) filters, working in conjunction with pre- and medium-efficiency filters to form a three-stage filtration system capable of intercepting over 99.97% of particles as small as 0.3μm.   Envelope Structure: Utilizing dust-proof, mildew-proof, and easy-to-clean materials (such as stainless steel and PVC roll materials), the junctions between walls, floors, and ceilings are rounded to prevent dust accumulation.   Ventilation and Differential Pressure Control: Maintaining positive pressure in the clean area by ensuring the supply air volume exceeds the exhaust air volume to prevent external contaminants from entering; a pressure gradient (typically 5-10 Pa) is established between areas of different cleanliness levels.   Cleanroom Auxiliary Systems: These include air showers for personnel entry, pass-through windows for material transfer, and clean benches, minimizing the introduction of contaminants through meticulous attention to detail.

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.