Explore our core industrial and customized air purification products manufactured to strict international quality control parameters.
In modern commercial, industrial, and clinical spaces, containment of airborne particulate matter is not just a safety standard—it is a critical pillar of operational integrity. The 20x25x4 HEPA filter configuration stands as the heavy-duty workhorse of secondary and terminal mechanical filtration. Unlike standard 1-inch or 2-inch residential filters, the 4-inch deep-pleat geometry provides a exponentially larger media surface area, translating to minimal initial airflow resistance and a prolonged dust-holding lifecycle.
Designed for heavy HVAC air handlers, cleanroom make-up air systems, and isolated clinical ventilation systems, these filters employ micro-glass or advanced composite synthetic media fibers. Through the combined interception, impaction, and diffusion mechanisms, our 20x25x4 filtration systems capture contaminants down to sub-micron scales (≥0.3 micrometers) with certified efficiencies matching and exceeding H13 standards.
Fractional Efficiency at 0.3μm
Deep Pleat Configuration
Initial Pressure Drop (W.G.)
A technical reference guide detailing dimension parameters, air flow capacities, pressure drop curves, and efficiency coefficients.
| Nominal Dimensions | Actual Dimensions (in) | Filter Class (EN 1822) | Rated Airflow (CFM) | Initial Resistance | Recommended Final Resistance | Primary Applications |
|---|---|---|---|---|---|---|
| 20x25x4 HEPA | 19.5 x 24.5 x 3.75 | H13 (≥99.95%) | 2000 CFM @ 500 FPM | 0.88 in. w.g. (220 Pa) | 1.8 in. w.g. (450 Pa) | Microelectronics, Medical, Labs |
| 20x25x4 Premium | 19.625 x 24.625 x 3.75 | H14 (≥99.995%) | 1800 CFM @ 450 FPM | 0.96 in. w.g. (240 Pa) | 2.0 in. w.g. (500 Pa) | Bio-Pharma, Isolation Rooms |
| 20x25x4 Medium | 19.5 x 24.5 x 3.75 | MERV 16 (ASHRAE) | 2000 CFM @ 500 FPM | 0.45 in. w.g. (112 Pa) | 1.2 in. w.g. (300 Pa) | Commercial HVAC Pre-Filtration |
Shenzhen Snow Peak Clean Technology Co., Ltd. is an integrated high-tech enterprise, specialized in air filtration products research and development, production, sales, import and export trade. We produce and supply: Pre-filter, pocket filter, HEPA filter, chemical filter; replacement HEPA filter, car cabin air filter, humidifier filter; pocket filter media, melt-blown composite filter media, and other high-performance filter materials.
We provide high quality air purification solutions and products for indoor air pollution control and air conditioning systems of civil and industrial buildings, microelectronics, pharmaceutical, laboratory, school, hospital clean room etc. Combined with self-developed patented technology, our sterilizing antiviral HEPA filter can effectively filtrate fine particles, so that PM2.5 concentration down to 10 micrograms/m3, 5 times better than national standard; effectively inhibit the breeding of microorganisms, sterilization rate up to 99.9%, and no secondary pollution, removal of H1N1 virus efficiency as high as 99.99%.
Having 15 years of international air purification technology experience as the background, our company has standardized production workshop, dust-free filter workshop and first-class technology of HEPA filters production line and inspection line, independent research and development of fully automatic air filter production line, equipped with AMADA CNC punch and CNC bending machine as well as many other advanced high-end equipment, provide a strong guarantee for production and quality of air filtration and purification products.
Years Industry Experience
Antiviral H1N1 Efficacy
Microbial Sterilization
Real-time look inside our advanced, fully-automated dust-free production workshops.
Precise hot melt dispensation for pleat stability.
CNC-controlled high tolerance dimensional sizing.
Ensuring zero frame-leak sealing integrity.
Multilayer processing for optimal dust capacity.
Equal spacing pleat folding structure.
Precision pleating for deep-bed HEPA layouts.
How multi-national procurement teams evaluate high-efficiency HEPA solutions to maintain continuous facility operations.
Global manufacturing facilities depend on standardizing standard dimension filters like 20x25x4 to ensure seamless dual-sourcing options without rebuilding air handling plenums.
From polyurethane gasketing to aluminum separator adjustments, B2B procurement engineers require high precision customization to meet tight static pressure tolerance parameters.
Procuring filters without verified test logs (such as EN1822 or ASHRAE 52.2 standards) carries huge risk. Snow Peak provides individualized unit test documentation for critical cleanrooms.
As global energy footprints and strict green building regulations tighten, the industrial filtration landscape undergoes a paradigm shift. Air filtration is no longer merely an isolation step; it is a vital part of thermodynamic HVAC optimization. Heavy-duty 20x25x4 HEPA setups play a central role in mitigating particulate drag, reducing motor energy draw across air handling systems, and aiding sustainability metrics.
For advanced semiconductor and fabrication lines (Microelectronics), standard HEPA configurations ensure yield security against particulate micro-bridging. Our engineering roadmap integrates advanced nanofiber substrates and low-outgassing polyurethane adhesives, ensuring that next-generation filters maintain structural integrity in corrosive cleanroom atmospheres.
In the bio-pharmaceutical sector, our patented antiviral technologies provide a dual layer of protection—mechanical filtration paired with active microbial neutralization, satisfying EU GMP Annex 1 guidelines and ensuring complete process containment.
Developing sub-100nm fiber webs to achieve high filtration efficiencies at lower mechanical resistance.
Moving toward biodegradable components and low carbon footprints in our automated filter production lines.
Deploying embedded pressure sensors within commercial filter housings for smart maintenance scheduling.
Strict quality controls and testing protocols to ensure maximum safety and regulatory compliance.
Every manufacturing step, from raw material procurement of fiberglass media to product packaging, complies with ISO-certified factory management processes.
Our particulate filters undergo standard aerosol challenges (DOP/DEHS) to determine local and overall efficiency metrics under rigorous safety criteria.
Our composite antimicrobial media is verified by independent, third-party labs to achieve >99.99% viral inactivation for medical and HVAC safety applications.
Insights from our senior design engineers to guide your facility planning and filter purchasing decisions.
Nominal sizing represents the rounded dimension of the mounting channel, while actual sizing is the true measurement of the filter frame. Standard actual dimensions for a 20x25x4 HEPA filter are 19.5" x 24.5" x 3.75". It is crucial to verify actual space clearances in your air handling unit (AHU) before placing large-scale custom orders to ensure a tight, leak-free gasket seal.
Pleat density controls the face velocity and air resistance parameters. A higher media surface area within a 4-inch depth reduces face velocity at the pleat face, resulting in a lower initial pressure drop. This lower resistance reduces the power demand on variable-frequency drive (VFD) fan motors, yielding significant energy savings over the system's operational lifecycle.
Antiviral effectiveness is verified using international bio-safety testing standards like ISO 18184 or modified AATCC tests. These tests expose the composite filter media to target viruses (such as Influenza H1N1) to measure the log reduction rate. Snow Peak filters achieve a certified 99.99% removal rate, neutralizing pathogens without releasing secondary contaminants or chemical outgassing.
HEPA-grade filters (H13/H14) introduce higher static resistance compared to standard MERV media. Prior to upgrading your commercial HVAC system to high-efficiency HEPA filters, confirm that your system's fan curve can support the increased pressure drop without reducing air flow rate (CFM) below critical design thresholds.
Explore our heavy-duty industrial separation elements, custom replacement HEPA modules, and raw media materials.
Snow Peak