Technical Principle: Corona Discharge and Electrostatic Deposition The industrial electrostatic precipitator (ESP) filter operates on the principles of electrophysics rather than physical barrier filtration. Traditional filters, such as glass fiber HEPA filters, physically intercept particles within a dense web of fibers. This increases resistance (pressure drop) as the filter loads. In contrast, an ESP filter charges passing particles and pulls them out of the airstream using electrostatic forces. The filtration cycle occurs in three distinct phases: 1. Corona Discharge & Ionization: The process begins in the ionizing stage of the ESP cell. High-strength ionizing wires, typically energized by a high-voltage direct current (HVDC) power source at 12kV to 15kV, generate an intense electric field. This high electric gradient accelerates free electrons, ionizing passing air molecules and generating a dense corona discharge. As airborne particles (such as grease droplets, dust, or smoke) pass through this zone, they collide with ionized gas molecules and acquire a strong positive electrostatic charge. 2. Particle Collection: The charged particles then travel immediately into the collector stage. This stage consists of a series of closely spaced, parallel metal plates. Alternating plates are energized with a lower positive DC voltage (usually 6kV to 7.5kV), while the adjacent plates are grounded. The resulting electrostatic field repels the positively charged particles away from the active plates and attracts them to the grounded collection plates. 3. Adhesion and Deposition: Once the particles make contact with the grounded collection plates, they lose their charge and adhere to the metal surface. For dry dust, adhesion is aided by molecular forces (van der Waals forces). For wet oil mist or commercial kitchen grease, the accumulated liquid forms a cohesive film that drains naturally down the vertical plates into a collection tray.   Because there is no fibrous barrier obstructing the airflow, the initial resistance of an ESP filter is exceptionally low (typically around 50 Pa) and remains relatively stable even as particulates accumulate. This makes ESP filters an extremely energy-efficient choice for handling heavy particulate and sticky aerosol loads.   Application Scenes Key application scenes include: · Commercial Kitchen Fumes: High-temperature cooking vaporizes grease, creating sub-micron grease aerosols. Standard filters block immediately and create a severe fire hazard. ESP systems remove these aerosols, protecting ductwork and complying with emissions standards. · Industrial Oil Mist and CNC Machining: Metalworking fluids and coolants volatilize during high-speed CNC milling and grinding, forming airborne oil mists. ESP systems recover these lubricants and keep the workshop air safe. · Welding and Soldering Smoke: Metal welding generates fine, hazardous metallic oxide fumes. An ESP captures these sub-micron particles, ensuring a safe respiratory environment for technicians. · Rubber and Plastics Manufacturing: Extrusion and curing lines emit heavy plasticizer smoke and vaporized paraffin, which are efficiently collected by industrial ESP units.   KLC Product Specifications Their systems are engineered for industrial durability, utilizing heavy-gauge aluminum alloy plates with a standard spacing of 8mm to 10mm. This plate spacing balances high electric field strength with resistance to arcing caused by excessive particulate accumulation. KLC's dual-stage industrial units are powered by advanced solid-state, high-frequency power supplies. These power packs automatically adjust voltage output to suppress arcing and prevent short circuits. Operating at an ionizing voltage of 12kV and a collection voltage of 6kV, these systems achieve a single-pass extraction efficiency of ≥95% (tested under DOP standards for particles down to 0.3 microns) and exceed ≥99% efficiency in double-pass configurations. This performance is achieved at a nominal face velocity of 2.5 m/s with an initial pressure drop of only 5ou Pa, dramatically reducing fan power consumption compared to HEPA-based filtration under similar dust loads.   Comparison Table: ESP Filter vs. Traditional HEPA Filter   Parameter / Feature Industrial Electrostatic Precipitator (ESP) Traditional HEPA Filter (e.g., H13/H14) Primary Capture Mechanism Electrostatic charging and plate deposition Mechanical sieving, interception, and diffusion Initial Resistance Very low (50–80 Pa) Moderate to high (150–250 Pa) Lifespan & Media Cost Washable; lasts up to 10 years (zero media replacement) Non-washable; replaced every 6–24 months (high cost) Ideal Contaminants Wet grease, oil mist, sticky exhaust, workshop smoke Dry, non-greasy airborne particulates and microorganisms Efficiency on Sub-micron Particles 95%–99% (highly velocity-dependent) 99.95%–99.995% (highly stable and independent of velocity) Maintenance Profile Regular chemical wash/dry cycles (1–3 months) Complete module replacement when terminal resistance is reached Fire Hazard Mitigation Captures grease, but arcing can occur if unmaintained Accumulates dry dust; high pressure drop increases risk if heated Operating Cost (Energy/Filters) Low fan energy, low filter cost, moderate washing labor High fan energy, high recurring filter purchase costs   Selection and Maintenance Advice Selection Advice 1. Volumetric Airflow Velocity: The face velocity through the ESP cells should not exceed 2.5 m/s. High velocities reduce the residence time of particles within the ionizing and collecting zones, leading to incomplete charging and a drop in efficiency. 2. Pre-Filtration Needs: For dusty environments, always install a mechanical pre-filter (such as a washable metal mesh or G4 pleated filter) upstream of the ESP. This captures large, coarse fibers and insects that would otherwise short-circuit the high-voltage cells. 3. Materials of Construction: Select high-grade aluminum alloy cells for general applications, or stainless steel (SUS304) for highly corrosive or acidic environments.     Cleaning and Maintenance Steps · Cleaning Cycle: Commercial kitchens and heavy machining shops require cell washing every 4 to 8 weeks. Light industrial smoke applications can extend this cycle to 12 weeks. · Step 1: Power Off and Grounding: Shut down the system. Wait at least 5 minutes for the capacitors to discharge. Open the cabinet door and use a grounding stick to touch the ionized wires and plates, ensuring zero residual charge. · Step 2: Cell Extraction: Carefully slide the ionizer and collector cells out of the tracks. · Step 3: Soaking: Submerge the cells in a hot water bath (60°C to 70°C) mixed with a specialized biodegradable alkaline degreasing surfactant. Let them soak for 30 to 60 minutes to dissolve baked-on grease and carbon deposits. · Step 4: Rinsing: Clean the cells using a low-pressure water washer. Avoid high-pressure jets, as they can bend the delicate collection plates or snap the tungsten ionizing wires. · Step 5: Inspection and Realignment: Inspect the cells. Straighten any bent plates and replace any broken ionizing wires. · Step 6: Complete Drying: Allow the cells to dry completely in a well-ventilated area for 24 hours. Placing wet cells back into the unit will trigger safety trips or damage the high-voltage power packs.   Frequently Asked Questions 1. How often should an industrial electrostatic precipitator filter be cleaned? The cleaning frequency of an industrial ESP filter depends entirely on the contaminant load of your process. For commercial kitchens and heavy machine tool workshops producing high volumes of oil mist and grease, cells should be cleaned every 4 to 6 weeks. For light manufacturing, electronic workshops, or commercial building exhaust where dry dust is the primary particulate, a maintenance interval of 12 weeks is standard. Allowing excessive buildup reduces collection efficiency and can trigger continuous electrical arcing. 2. What voltage is typically used in industrial ESP air cleaners? Industrial ESP air cleaners operate on high-voltage direct current (HVDC) split into two distinct stages. The ionizing section utilizes a very high voltage—typically 12kV to 15kV—to create a strong corona discharge that ionizes passing air molecules. The collection section uses a lower but still substantial voltage, usually 6kV to 7.5kV, to establish the electrostatic field required to attract the charged particulates to the grounded plates without causing dielectric breakdown of the air. 3. Can ESP filters remove gaseous odors and volatile organic compounds (VOCs)? No, standard ESP filters are designed to capture solid particulates, wet aerosols, oil mist, and grease droplets. They cannot capture individual gas-phase molecules such as VOCs, kitchen odors, or toxic fumes. To achieve comprehensive air purification, facilities must combine an ESP system with gas-adsorption filters, such as activated carbon beds or photo-catalytic oxidation (PCO) systems, which are placed downstream of the ESP. 4. Why do ESP filters produce a snapping or crackling sound during operation? A snapping or crackling sound, also known as "arcing", occurs when a high-voltage spark jumps across the air gap between an ionizing wire (or positive plate) and a grounded plate. Occasional snapping is normal, often caused by a large particle, insect, or water droplet passing through. However, continuous or rapid snapping indicates that the collector plates are overloaded with dirt, a plate is bent and too close to another, or the cell is damp, requiring immediate maintenance. 5. What is the difference between single-pass and double-pass ESP systems? A single-pass ESP contains one set of ionizer-collector cells. It typically achieves a particulate and grease extraction efficiency of 90% to 95%, which is sufficient for basic exhaust configurations. A double-pass ESP features two ionizer-collector cell modules arranged in series within the airflow path. This arrangement doubles the residence time of particulates in the electrostatic field, boosting extraction efficiency to 99% or higher, which is essential for sensitive urban areas. 6. Are washable electrostatic filters as efficient as HEPA filters for sub-micron particles? Washable ESP filters can achieve high efficiencies (95% to 99%) for fine particulates, including sub-micron smoke, under optimal conditions. However, their efficiency is highly sensitive to airflow velocity and maintenance. If the air speed is too high, particles pass through too quickly to be charged or captured. Traditional HEPA filters (H13/H14) maintain a stable, certified efficiency of 99.95% to 99.995% regardless of dirt buildup, but they suffer from high pressure drops and are non-washable. 7. What are the electrical safety risks associated with industrial ESP filters? Because ESP filters operate at high voltages (12kV+), they present electrical shock risks if safety protocols are ignored. Modern systems include safety interlocks that automatically cut off power when the access door is opened. However, the cells can retain static charge. Maintenance personnel must always turn off the system, wait several minutes, and use a grounding tool to discharge any residual electricity from the plates before removing the cells. 8. How does plate spacing affect the filtration efficiency and pressure drop of an ESP? Plate spacing is a critical design variable. Narrower plate spacing (e.g., 6mm to 8mm) allows for a more compact filter cell and a stronger electrostatic field at lower voltages, but it increases the risk of short-circuiting due to dirt bridges and is harder to clean. Wider spacing (10mm to 12mm) reduces the risk of arcing and handles high dust loads better, but requires higher voltages to maintain efficiency. In both cases, pressure drop remains extremely low because there is no dense filter media obstructing airflow. 9. Conclusion and Recommendations For B2B buyers looking to eliminate heavy grease, workshop smoke, or machining oil mist while minimizing energy expenses, an industrial ESP filter is the most cost-effective and sustainable solution. Unlike disposable media filters, its washable cells eliminate ongoing replacement costs, and its ultra-low pressure drop significantly lowers fan utility bills. To ensure long-term reliability and compliance with environmental regulations, it is highly recommended to partner with an established, vertically integrated supplier who holds accredited quality certifications.

A modular cleanroom (or portable cleanroom) offers a flexible, cost-effective alternative to traditional "built-in" facilities. Whether you need an ISO 5 micro-environment or an ISO 8 assembly hall, the modular approach allows for rapid deployment and future expansion.   At KLC International, we provide "Turnkey Modular Kits" that include everything from the structure to the validation papers. Here is the breakdown of what you need and what it costs.     Equipment Checklist by ISO Class   Equipment ISO 5 (Ultra-Clean) ISO 7 (Standard) ISO 8 (Basic) Airflow Source 70-100% FFU Coverage 15-25% FFU Coverage 5-10% FFU or AHU Filter Grade U15 ULPA / H14 HEPA H14 HEPA H13 HEPA Walls Hardwall (Acrylic/PVC/SUS) Hardwall or Softwall Softwall (Anti-static) Entry System Air Shower + Pass Box Pass Box Strip Curtain / Door Flooring Raised Floor / Epoxy Epoxy / Raised Floor Epoxy     Estimated Setup Costs (2026 Market Data) Note: Prices are estimates based on a 20m² standard footprint. Costs per m² decrease as area increases.   ISO Class Price Range (USD/m²) Total Est. Cost (20m²) Build Timeline ISO 5 $800 – $1,500 $16,000 – $30,000 8 – 12 Weeks ISO 6 $500 – $900 $10,000 – $18,000 6 – 10 Weeks ISO 7 $300 – $600 $6,000 – $12,000 4 – 8 Weeks ISO 8 $150 – $350 $3,000 – $7,000 3 – 6 Weeks     The KLC One-Stop Advantage 1. Modular Structure: Aluminum or SUS 304 frames that bolt together in hours. 2. Integrated Controls: One touch-screen to control FFUs, lighting, and pressure. 3. Fast Validation: Pre-engineered to pass ISO 14644-1 audits on day one. 4. Global Shipping: Modular components are packed in standard crates for easy export.     FAQ: Frequently Asked Questions 1. What is a modular cleanroom?It is a freestanding cleanroom built from pre-fabricated components like aluminum frames, fan filter units (FFUs), and panel walls. 2. How long does it take to build a modular cleanroom?Depending on size and ISO class, a small room (20m²) can be manufactured and shipped in 4 weeks and installed on-site in 3-5 days. 3. Is a modular cleanroom as "clean" as a traditional one?Yes. If engineered correctly with high FFU coverage and HEPA filters, a modular room can easily achieve ISO 5 or even ISO 4 standards. 4. Can I move my modular cleanroom?Yes. That is the primary advantage. You can disassemble, move, and reassemble it in a new location or expand its size. 5. What flooring is best for a modular cleanroom?Anti-static PVC or Epoxy-coated concrete are the most common. For ISO 5, a raised perforated floor is recommended for vertical laminar flow. 6. Do I need an air shower for a modular room?For ISO 6 and cleaner, an air shower is highly recommended to protect the internal environment from personnel-borne dust. 7. How do I maintain a modular cleanroom?Regularly monitor pressure gauges, perform monthly surface cleaning, and replace HEPA filters every 2-3 years. 8. What is the difference between hardwall and softwall?Hardwall (Acrylic/PC) is more durable and maintains pressure better. Softwall (PVC curtains) is cheaper and allows for easy equipment movement.     Build your clean zone today.View KLC Modular Cleanroom Projects or Request a 3D Layout and Quote.

While both the Air Shower and the Pass Box are essential for cleanroom contamination control, they serve different masters. The Air Shower is the gatekeeper for personnel, using high-velocity air to "scrub" particles off clothing. The Pass Box is the gatekeeper for materials, allowing for the transfer of goods without personnel movement. Choosing the right combination is critical for GMP compliance and operational efficiency. Here is the definitive comparison.     Side-by-Side Comparison   Feature Air Shower Pass Box Primary Purpose Personnel Decontamination Material Transfer Working Principle 20-25m/s Air Jet "Scrubbing" Physical Barrier / HEPA Purge Installation Site Between Locker Room & Cleanroom Between Rooms of Different Grades Dwell Time 10 – 20 Seconds Instant (Static) / 3-5 Min (Dynamic) GMP Role Reduces Bio-burden on Gowns Prevents Cross-contamination Typical Cost (USD) $2,500 – $6,000 $400 – $2,000 Power Requirement High (High-pressure blowers) Low (Static) / Moderate (Dynamic)   When to Use Which? 1. Air Shower: Mandatory for personnel entering ISO 6 or cleaner zones. It serves as a psychological and physical "reset" for employees, ensuring they are properly gowned and cleaned before entry. 2. Pass Box: Mandatory for any cleanroom (ISO 5-8). Transferring materials through a pass box reduces the number of times personnel must enter and exit, which is the #1 source of contamination. 3. Dynamic vs. Static Pass Box: If transferring between a non-clean and clean area, use a Dynamic Pass Box (with its own HEPA filtration). If transferring between two clean areas of the same grade, a Static Pass Box is sufficient.     4 Synergy Benefits of Using Both Minimized Personnel Movement: Goods go through the wall, people through the shower. Airtight Integrity: Both units feature electronic interlocking doors to ensure one door is always closed. Pressure Maintenance: They act as airlocks, preventing large pressure drops when doors open. Regulatory Compliance: Meets EU GMP Annex 1 and FDA requirements for material/personnel flow.     FAQ: Frequently Asked Questions 1. What is the difference between an air shower and a pass box?An air shower is for people; a pass box is for things. Air showers use high-speed air; pass boxes are mostly static airlocks (unless dynamic). 2. Do I need both an air shower and a pass box?Yes. In almost any professional cleanroom (Pharma, Semi, Lab), you need a way for people to enter and a separate way for materials to enter to maintain ISO standards. 3. What wind speed is required for an air shower?For effective particle removal, a nozzle velocity of at least 20-25 m/s is required. KLC units typically reach 22-25 m/s. 4. How long should an air shower cycle last?The industry standard is 10 to 15 seconds. Cycles shorter than 10 seconds are generally ineffective at removing fine dust. 5. What is a dynamic pass box?A dynamic pass box has a built-in fan and HEPA filter to actively clean the air inside the box and maintain a higher pressure than the surrounding rooms. 6. Does a pass box need HEPA filtration?Only if it is a dynamic pass box used for transfers into high-grade areas (Grade A/B). Static pass boxes do not have filters. 7. What is the GMP requirement for pass boxes?GMP requires that pass boxes have interlocking doors to prevent both from opening at once and, in some cases, UV sterilization or HEPA purging. 8. Can a pass box replace an air shower?No. You cannot pass a person through a pass box, and passing large materials through an air shower is inefficient and can damage the nozzles. 9. How often should air shower nozzles be cleaned?Monthly. Nozzles can accumulate dust over time, which reduces air velocity and can lead to "re-contamination." 10. What is the typical cost of an air shower vs a pass box?A standard air shower costs $3,000-$5,000. A standard static pass box costs $500-$800, while a dynamic one can cost $1,500-$2,000.     Optimize your cleanroom traffic.View KLC’s Air Shower and Pass Box Models or Request a custom dimensions quote.

Air Changes Per Hour (ACH) is the number of times the entire volume of air in a room is replaced with filtered air within 60 minutes. It is the most critical calculation for achieving and maintaining ISO cleanliness levels. If your ACH is too low, you won't meet your particle count targets. If it's too high, you are wasting energy and money. Here is how to get it right.     The ACH Formula To calculate the ACH of an existing room:ACH = (Total Airflow in m³/h) ÷ (Room Volume in m³) To calculate the required airflow for a new design:Required Airflow (m³/h) = Room Volume (m³) × Target ACH   Recommended ACH by ISO Class   ISO Class US 209E Equivalent Recommended ACH ISO 5 Class 100 240 – 480 ISO 6 Class 1,000 150 – 240 ISO 7 Class 10,000 60 – 90 (General) / 120 (Pharma) ISO 8 Class 100,000 20 – 45     Real-World Calculation Examples Example 1: Pharmaceutical ISO 7 Fill Room Room Size: 10m (L) × 8m (W) × 3m (H) = 240 m³ Target ACH: 100 Calculation: 240 m³ × 100 ACH = 24,000 m³/h FFU Requirement: If using FFUs with 1,200 m³/h capacity, you need 20 FFUs.   Example 2: Electronics ISO 8 Assembly Area Room Size: 20m (L) × 15m (W) × 3m (H) = 900 m³ Target ACH: 30 Calculation: 900 m³ × 30 ACH = 27,000 m³/h FFU Requirement: If using FFUs with 2,000 m³/h capacity, you need 14 FFUs.     3 Factors That Influence ACH Selection 1. Personnel Load: More people = more particles = higher ACH needed. 2. Process Activity: High-speed machinery generates more dust than manual assembly. 3. Recovery Time: How fast must the room "clean itself" after a door opening? Higher ACH improves recovery time.     FAQ: Frequently Asked Questions 1. What is cleanroom air changes per hour?It is a measure of how quickly the HVAC system replaces the room's air with fresh, filtered air. It is expressed as the number of cycles per hour. 2. How do I calculate ACH for my cleanroom?Multiply the room's length, width, and height to get the volume, then divide your total measured supply airflow (from all diffusers/FFUs) by that volume. 3. Is higher ACH always better?No. Once you meet your ISO class requirements, additional ACH only increases energy consumption and filter wear without adding value. 4. What is the minimum ACH for an ISO 8 cleanroom?Most standards recommend a minimum of 20 ACH for ISO 8, though some light-duty electronics labs can operate at 15 ACH. 5. How does FFU quantity relate to ACH?FFUs provide the airflow. The more FFUs you have, the higher the total airflow, and thus the higher the ACH. 6. Do return air vents affect the ACH calculation?The calculation is based on supply air. However, return vents must be sized to handle the same volume to prevent over-pressurization. 7. Does the height of the ceiling matter?Yes. A higher ceiling increases the room volume, requiring more total airflow to achieve the same ACH compared to a lower ceiling. 8. Can I reduce ACH during the night?Yes. This is called "setback" or "night mode." Many labs drop ACH by 50% when unoccupied to save energy while maintaining positive pressure.     Get your cleanroom math right. Use KLC’s Online ACH Calculator or Request a custom design proposal.