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Medium-Efficiency Air Filters | YONGFAN
Air Filtration · Intermediate Stage (F5–F9 / ISO ePM10, ePM2.5, ePM1)

Medium-Efficiency Air Filters: Protect Final Stages & Manage System Pressure

Medium-efficiency filtration is where an HVAC system either protects its final filters—or makes them carry dust they should never have seen.

Compare YONGFAN ZF5(6), ZF7(8), ZF9 bag filters, ZZH compact V-bank modules, ZDZ mini-pleats and ZYG separator box filters across airflow (730–3,600 m³/h), initial static pressure (50 Pa to 140 Pa), depths (295 mm & 600 mm), and synthetic vs. glass-fibre media.

6 Families ZF5(6) · ZF7(8) · ZF9 · ZZH · ZDZ · ZYG
Initial ΔP 50 Pa – 140 Pa
Depth Formats 295 mm (Rigid) · 600 mm (Bag)
Media Formats Synthetic Pocket · Mini-Pleat · Glass Box
Choose a Medium-Efficiency Filter Review Selection Principles
YONGFAN medium-efficiency pocket air filter
Intermediate Stage Engineering Balancing Downstream HEPA Life, Clean Pressure Drop & AHU Depth
01 / Pressure Management & Final Filter Protection

Medium-Filter Selection Decides What Reaches the Final Stage

A primary filter can stop coarse dust and debris, but it cannot carry the full fine-particle load of a clean-air system. If the next stage is too weak, fine contamination fouls coils and terminal filters. If it is too restrictive, fan energy climbs.

Accelerated HEPA Filter Blinding

If the medium filter fails to capture fine particle mass, the terminal HEPA filter loads prematurely. Replacing expensive, delicate terminal HEPA elements frequently creates severe O&M overhead.

Impact: Shortened terminal filter replacement intervals

Premature Fan Pressure Limitation

Choosing the highest nominal medium grade without verifying initial and dirty resistance causes the AHU fan to reach static pressure limits while filters are still relatively clean.

Impact: Inadequate design airflow & excessive kW draw

AHU Section Depth Mismatch

A 600 mm bag filter needs substantial depth inside the AHU to inflate pockets without fluttering or colliding. In shallow banks, compact V-banks or mini-pleat elements (295 mm) prevent pocket collapse.

Impact: Structural pocket collapse & flow bypass

Media Shedding & Environmental Limits

Industrial or process airstreams containing chemical fumes, oil mist, or temperatures up to 80 °C require robust synthetic pockets, mini-pleats, or aluminum-separated glass-fibre packs (ZYG).

Impact: Thermal degradation & downstream fiber release

The Correct Choice Starts with Complete System Constraints

Medium filtration is not simply “the filter between G4 and HEPA.” It is an integrated pressure-management, geometry, and dust-loading engineering decision.

01 Required Filtration Grade (F5–F9 / ISO ePM)
02 Allowable Clean & Final ΔP Budget
03 Available Filter-Bank Depth (295 vs 600 mm)
04 Downstream Target & Maintenance Plan
02 / Engineering Principles

Efficiency Grade and Pressure Drop Must Be Read Together

A filter efficiency figure does not tell you how hard the fan must work. Initial resistance and rated airflow are separate specifications and should be compared beside the efficiency figure.
Principle 01 / Particle Retention

Efficiency Grade Progression

YONGFAN’s medium range scales from F5 (40–45% counting) to F9 (98% counting). Legacy F-grades describe specific counting or gravimetric tests; for ISO 16890 projects, confirm the required ePM1, ePM2.5, or ePM10 test report rather than converting by assumption.

Principle 02 / Fan Static Head

Initial Clean Resistance (ΔP)

Moving from F5 (50 Pa) to F8 (100 Pa) or F9 (120 Pa) doubles initial fan static resistance. Higher efficiency is never a “free upgrade”—each grade step must be verified against available fan curve margin and dirty-filter pressure allowance.

Principle 03 / Packaging & Depth

Geometry & Airflow Capacity

A 600 mm bag utilizes depth for large media area at low clean resistance. Where AHU depth is limited to 295 mm, compact V-banks (ZZH) or mini-pleats (ZDZ) package high media area, delivering up to 3,600 m³/h per standard 592/595 mm face cell.

Published Initial Resistance Comparison by Family & Grade

These figures reflect different media formats, frame depths, and filtration duties — not a ranking of product quality.

Clean Filter Baseline @ Rated Airflow
ZF5(6) Bag Filter
50 / 55 Pa
600 mm Bag · F5 (40–45%) / F6 (60–70%) · Low ΔP
ZF7(8) Bag Filter
96 / 100 Pa
600 mm Bag · F7 (80–85%) / F8 (90–95%) · Synthetic
ZF9 Bag Filter
120 Pa
600 mm Bag · F9 (98% Counting) · High Intermediate
ZZH V-Bank Module
≤120 Pa
295 mm Rigid · F6–F9 · High Airflow (3,600 m³/h)
ZDZ-45 Mini-Pleat
≤95 Pa
295 mm Rigid · 45% Stated Efficiency · Compact Depth
ZDZ-65 Mini-Pleat
≤105 Pa
295 mm Rigid · 65% Stated Efficiency · Fume / Mist Duty
ZDZ-85 / 95 Mini-Pleat
≤120 / 140 Pa
295 mm Rigid · 85% / 95% Stated Efficiency · Multi-Grade
ZYG Separator Box
≤125 Pa
295 mm Box · Glass Fibre · 85% · 80 °C / 80% RH Max
1. Required Stage Intermediate fine particle protection
2. Pressure Allowance Clean 50–140 Pa & Fan Curve Limit
3. Geometry & Bank 600 mm Bag vs. 295 mm Compact Module
4. Media & Environment Synthetic pocket, mini-pleat or glass box
03 / Product Lineup

Choose the Medium-Filter Family by Construction and Duty

YONGFAN’s medium-efficiency range covers three main construction routes: extended bag filters, compact V-bank modules, and rigid pleated/separator box filters.
Family 01 · ZF5(6) Series 600 mm Bag · F5 / F6

ZF5(6) Medium Bag Air Filter

The ZF5(6) family is the starting point in YONGFAN’s medium-stage bag range. It provides an economical intermediate stage with very low clean resistance: 50 Pa for F5 (40–45% counting efficiency) and 55 Pa for F6 (60–70% counting efficiency).

The extended 600 mm pocket geometry creates a large media area at modest static pressure drop, making ZF5(6) ideal where the AHU has adequate track depth and the system requires a cost-effective intermediate barrier ahead of finer filtration.

Efficiency Grades
F5 (40–45%) · F6 (60–70%) [Counting]
Initial Clean Resistance
50 Pa (F5) · 55 Pa (F6)
Standard Pocket Depth
600 mm (5, 6, 8 pockets)
Airflow Rating
1,300 – 3,200 m³/h
Maintenance Condition Note: Supplier material describes ZF5(6) as reusable for multiple washes. This should be treated as a maintenance condition rather than a universal service guarantee: washing method, contaminant type, and media condition must be inspected before reinstallation.
View ZF5(6) Details Request ZF5(6) Sizing
ZF5(6) Standard Model Ratings
ZF5(6)-13 490 × 295 × 600 mm (5P) 1,300 m³/h
ZF5(6)-22 490 × 490 × 600 mm (5P) 2,200 m³/h
ZF5(6)-16 595 × 295 × 600 mm (6P) 1,600 m³/h
ZF5(6)-27 595 × 490 × 600 mm (6P) 2,700 m³/h
ZF5(6)-32 595 × 595 × 600 mm (8P) 3,200 m³/h

*Standard 600 mm pocket depth; custom face sizes & pocket counts available.

Family 02 · ZF7(8) Series 600 mm Bag · F7 / F8

ZF7(8) Synthetic-Fibre Bag Air Filter

The ZF7(8) family keeps the 600 mm bag format but increases filtration duty significantly. YONGFAN publishes initial resistance of 96 Pa for F7 (80–85% counting efficiency) and 100 Pa for F8 (90–95% counting efficiency).

Constructed from lint-free synthetic fibre media with up to 10 pockets, ZF7(8) prevents fibre shedding into the downstream airstream. It is suited for general commercial HVAC, clean manufacturing, and pre-filtration ahead of final HEPA cleanroom stages.

Efficiency Grades
F7 (80–85%) · F8 (90–95%) [Counting]
Initial Clean Resistance
96 Pa (F7) · 100 Pa (F8)
Media Material
Non-shedding synthetic fibre
Pocket Count
8 Pockets (490 mm) · 10 Pockets (595 mm)
Test Method Clarification: Summary descriptions mention average efficiency as 85% (F7) / 95% (F8) using gravimetric wording, while technical tables specify counting method (80–85% / 90–95%). Projects requiring strict compliance should request the exact test report for the selected model.
View ZF7(8) Details Request ZF7(8) Sizing
ZF7(8) Standard Model Ratings
ZF7(8)-13 490 × 295 × 600 mm (8P) 1,300 m³/h
ZF7(8)-22 490 × 490 × 600 mm (8P) 2,200 m³/h
ZF7(8)-16 595 × 295 × 600 mm (10P) 1,600 m³/h
ZF7(8)-27 595 × 490 × 600 mm (10P) 2,700 m³/h
ZF7(8)-32 595 × 595 × 600 mm (10P) 3,200 m³/h

*High dust-holding synthetic pocket filter for cleanroom AHU pre-stages.

Family 03 · ZF9 Series 600 mm Bag · F9 (98% Counting)

ZF9 High-Grade Bag Air Filter

The ZF9 family represents the highest-grade bag filter group in YONGFAN’s medium range. Published with 120 Pa initial clean resistance and 98% efficiency by stated counting method, it removes high proportions of fine sub-micron particles.

YONGFAN targets pharmaceutical, semiconductor, electronics, precision machinery, and food-industry facilities where maximizing upstream particulate removal extends the operational lifespan of expensive terminal HEPA/ULPA filters.

Efficiency Grade
F9 (98% by counting method)
Initial Clean Resistance
120 Pa
Pocket Depth
600 mm (4, 6, 8, 10 pockets)
Target Sectors
Pharma, Electronics, Machinery, Food
Fan Head Warning: A 120 Pa clean baseline means F9 should never be substituted automatically for F7 or F8 without checking fan curves. A filter that improves capture but pushes the fan beyond its operating limit compromises system airflow.
View ZF9 Details Request ZF9 Sizing
ZF9 Standard Model Ratings
ZF9-13 490 × 295 × 600 mm (4P) 1,300 m³/h
ZF9-22 490 × 490 × 600 mm (4P) 2,200 m³/h
ZF9-16 595 × 295 × 600 mm (6P) 1,600 m³/h
ZF9-27 595 × 490 × 600 mm (8P) 2,700 m³/h
ZF9-32 595 × 595 × 600 mm (10P) 3,200 m³/h

*Top-tier bag filtration ahead of cleanroom terminal equipment.

Family 04 · ZZH Series 295 mm V-Bank · High Airflow

ZZH Medium Combined V-Bank Air Filter

The ZZH Medium Combined Filter uses a rigid V-bank multi-panel construction instead of unsupported long pockets. Available in grades from F6 through F9, YONGFAN publishes initial clean resistance of ≤120 Pa at F7.

ZZH solves depth limitations by packaging extended media into a rigid 295 mm-deep module. It delivers high face velocity capability: the full-size ZZH-36 is rated at 3,600 m³/h (higher than the 3,200 m³/h top rating of bag filters), making it ideal for compact retrofit AHUs.

Efficiency Range
F6 (50–60%) · F7 (80–85%) · F8 (90–95%) · F9 (>90%)
Initial Clean Resistance
≤120 Pa (at F7 rating)
Frame Depth
295 mm (Rigid V-Bank Module)
Maximum Airflow
Up to 3,600 m³/h (ZZH-36)
Geometric Benefit: Choose ZZH when the AHU lacks the 600 mm clear depth required for bag filters, or when rigid modules are preferred for high face velocity and turbulent airflow stability.
View ZZH Details Request ZZH Sizing
ZZH Standard Model Ratings
ZZH-18 295 × 592 × 295 mm (Half-Size) 1,800 m³/h
ZZH-36 592 × 592 × 295 mm (Full-Size) 3,600 m³/h

*Compact 295 mm depth saves AHU section length while handling up to 3,600 m³/h.

Family 05 · ZDZ Series 295 mm Mini-Pleat · 4 Grades

ZDZ Medium Pleated Mini-Pleat Filter

The ZDZ Medium Pleated Filter utilizes a compact mini-pleat construction with four efficiency grades: ZDZ-45 (45%, ≤95 Pa), ZDZ-65 (65%, ≤105 Pa), ZDZ-85 (85%, ≤120 Pa), and ZDZ-95 (95%, ≤140 Pa).

ZDZ is engineered for workshop and AHU environments containing dust, oil mist, and chemical fumes, including precision machinery, semi-finished goods, and light industrial processing. It provides multiple efficiency/resistance balances inside a single 295 mm envelope.

Grade Options
45% (≤95 Pa) · 65% (≤105 Pa) · 85% (≤120 Pa) · 95% (≤140 Pa)
Frame Depth
295 mm Mini-Pleat Box
Rated Airflow Range
1,200 – 3,600 m³/h
Application Duty
Dust, oil mist, and light chemical fumes
Sizing Warning: External dimensions do not dictate airflow rating. For example, both ZDZ-12-95 and ZDZ-25-95 measure 595×595×295 mm, but one is rated at 1,200 m³/h and the other at 2,500 m³/h due to pleat density. Model code and airflow must stay paired.
View ZDZ Details Request ZDZ Sizing
ZDZ Standard Model Configurations
ZDZ-12-95 595 × 595 × 295 mm (95%) 1,200 m³/h
ZDZ-17-95 490 × 490 × 295 mm (95%) 1,700 m³/h
ZDZ-25-95 595 × 595 × 295 mm (95%) 2,500 m³/h
ZDZ-16-85 295 × 595 × 295 mm (85%) 1,600 m³/h
ZDZ-23-85 490 × 490 × 295 mm (85%) 2,300 m³/h
ZDZ-33-85 595 × 595 × 295 mm (85%) 3,300 m³/h
ZDZ-18-65/45 295 × 595 × 295 mm (65/45%) 1,800 m³/h
ZDZ-24-65/45 490 × 490 × 295 mm (65/45%) 2,400 m³/h
ZDZ-36-65/45 595 × 595 × 295 mm (65/45%) 3,600 m³/h

*Mini-pleat layout offering fine trade-off between clean ΔP and retention.

Family 06 · ZYG Series 295 mm Box · Glass-Fibre Separator

ZYG Medium Separator Box Air Filter

The ZYG Medium Box-Type Filter uses glass-fibre paper media arranged with corrugated aluminum-foil separators enclosed within a galvanized-steel frame. It publishes 85% counting efficiency with initial clean resistance of ≤125 Pa.

The self-supporting aluminum separator construction provides high structural stability under varying air pressures. With published limits of 80 °C maximum operating temperature and 80% relative humidity, it is tailored for industrial ventilation requiring glass-fibre media.

Efficiency & Clean ΔP
85% (Counting) · ≤125 Pa Initial
Materials
Glass-fibre paper · Alum foil · GI steel
Operating Limits
Max 80 °C · Max 80% Relative Humidity
Sealant
Polyurethane structural seal
Environmental Limits Boundary: The 80 °C and 80% RH limits must be strictly respected. Do not apply ZYG into saturated air or higher-temperature process streams without confirming sealant and separator suitability.
View ZYG Details Request ZYG Sizing
ZYG Standard Model Ratings
ZYG-7.3 295 × 295 × 295 mm 730 m³/h
ZYG-15 295 × 592 × 295 mm 1,500 m³/h
ZYG-21 490 × 490 × 295 mm 2,100 m³/h
ZYG-30 592 × 592 × 295 mm 3,000 m³/h

*Rigid aluminum separator box for glass-fibre specification environments.

04 / Selection Matrix

Medium-Filter Family Routing Table

Cross-reference all six YONGFAN medium-efficiency filter families by construction type, published efficiency range, initial clean resistance, standard airflow boundary, and the best first question to ask.
Product Family Construction Published Efficiency Initial Resistance Standard Airflow Boundary Best First Question Specification Action
ZF5(6) Bag Filter F5 / F6
600 mm Synthetic Bag F5 (40–45%) / F6 (60–70%)
50 / 55 Pa
 1,300–3,200 m³/h Is lower resistance more important than higher grade? Configure ZF5(6)
ZF7(8) Bag Filter F7 / F8
600 mm Synthetic-Fibre Bag F7 (80–85%) / F8 (90–95%)
96 / 100 Pa
 1,300–3,200 m³/h Do I need higher-efficiency non-shedding bags before final filtration? Configure ZF7(8)
ZF9 Bag Filter F9 (98%)
600 mm Extended Bag F9 (98% Counting)
120 Pa
 1,300–3,200 m³/h Can the fan carry F9 clean and dirty resistance? Configure ZF9
ZZH V-Bank Filter F6–F9
295 mm Rigid V-Bank Module F6 to F9 (50% to >90%)
≤120 Pa (F7)
 1,800–3,600 m³/h Is AHU depth limited or is higher airflow per face required? Configure ZZH
ZDZ Mini-Pleat Filter 45–95%
295 mm Mini-Pleat Module 45%, 65%, 85%, 95% Stated
≤95–140 Pa
 1,200–3,600 m³/h Which efficiency / airflow balance fits the same compact depth? Configure ZDZ
ZYG Separator Box 85% Glass
295 mm Separator Box (GI Frame) 85% Stated Counting Method
≤125 Pa
 730–3,000 m³/h Do rigid separator build and 80 °C / 80% RH limits fit? Configure ZYG
Criterion 01

Available AHU Depth

If the section allows 600 mm, ZF bag filters provide maximum media area. If limited to 295 mm, choose ZZH, ZDZ, or ZYG.

Criterion 02

Airflow per Filter Face

ZF bags handle up to 3,200 m³/h. ZZH and high-capacity ZDZ handle up to 3,600 m³/h per 592/595 mm face, reducing module count.

Criterion 03

Maintenance Access

Long bags require rear clearance for pocket expansion and inspection. Rigid modules slide neatly through defined side/front access doors.

Criterion 04

Process Environment

Synthetic bags resist standard dust; ZDZ handles oil mist and chemical fumes; ZYG provides glass-fibre media up to 80 °C and 80% RH.

*This table is a routing tool, not a substitute for the selected model datasheet. Source documents use legacy F classes and percentage counting methods; confirm against project test specifications.
05 / Procurement Protocol

Information Required for a Medium-Filter Quotation

Do not send only “F7 filter, 595×595.” That leaves out construction, depth, airflow and resistance that decide whether the product will function properly in your AHU.
STEP 01

Required Grade & Standard

Specify the target classification (e.g. F5–F9 or ISO 16890 ePM1/ePM2.5/ePM10) and required test standard basis.

STEP 02

Airflow & Bank Sizing

Provide rated airflow per filter cell or total bank airflow (m³/h or CFM) to confirm face velocity and clean ΔP.

STEP 03

Bank Face & Usable Depth

State opening W × H dimensions and maximum available depth clearance (600 mm bag vs 295 mm compact).

STEP 04

Pressure & Environmental Limits

Provide allowable initial/final ΔP, downstream filter type (HEPA/terminal), air temperature, humidity, and contaminants.

Engineering Handoff

10 Parameters for Accurate Medium-Filter Quotes

Send your available system data. YONGFAN application engineers will verify face velocity, static pressure drop, and dimensional compatibility.

1. Required Filter Grade / Project Standard
2. Rated Airflow per Filter or Total Bank
3. Filter Face Size (W × H mm)
4. Maximum Available Depth (295 / 600 mm)
5. Allowable Initial & Final Pressure Drop
6. Downstream Filtration Stage (HEPA/FCU)
7. Air Temperature & Relative Humidity
8. Contaminant Type (Dust, Oil Mist, Fumes)
9. Disposable, Washable or Rigid Preference
10. Existing Frame Details for Retrofit
06 / Manufacturing Consistency

YONGFAN Filter Production and Verification Controls

YONGFAN’s medium-filter documents describe dedicated in-house filter manufacturing that includes precision pleating, ultrasonic pocket welding, hot-melt separator bonding, and rigorous aerodynamic quality controls.
Automated Assembly

Pleat Geometry & Pocket Forming

In-house pocket welding, mini-pleat hot-melt lines, and aluminum-separator forming control pleat count, height, and spacing, ensuring uniform airflow velocity distribution.

Material Verification

Media & Frame Integrity

Synthetic pocket media, glass-fibre paper, extruded aluminum, and galvanized frames undergo incoming checks for tensile strength, thickness, and resistance before assembly.

Standards Testing

ISO 16890, EN 779 & GB/T 14295

Initial resistance and fractional efficiency are tested using calibrated counting and gravimetric test rigs to ensure published ratings match delivered hardware.

Traceability

100% Inspection & Labelling

Every finished unit is inspected for dimensional tolerances, gasket compression, and frame rigidity, and labelled with model code, grade, and size for repeat reordering.

7–15 Days Dispatch: Standard catalog model sizes are held in inventory for rapid export packing and international delivery. Bespoke Engineering: Custom W × H × D dimensions, non-standard pocket depths, and special frame alloys produced on order.
07 / Engineering Knowledge

Medium-Efficiency Filter Frequently Asked Questions

Direct technical answers to common questions regarding intermediate filter selection, pressure drops, washable claims, and replacement considerations.

Which YONGFAN medium filter has the lowest published initial resistance?

Among the standard medium families, ZF5(6) has the lowest published initial resistance: 50 Pa for F5 and 55 Pa for F6. However, that does not make it the right choice where project specifications require F7, F8, or F9-level downstream particle protection.

What is the difference between ZF7(8) and ZF9?

Both are 600 mm bag-filter families. ZF7(8) covers F7 and F8 with published initial resistance of 96 and 100 Pa (80–95% counting efficiency), while ZF9 is the higher bag stage at 120 Pa and 98% stated counting efficiency for stricter particulate control.

When should I choose ZZH instead of a bag filter?

Choose ZZH when the project favors a rigid V-bank module, the AHU does not have 600 mm of bag depth clearance, or higher airflow per full-size filter face is needed (up to 3,600 m³/h). ZZH is 295 mm deep in standard sizes.

What is the main advantage of ZDZ?

ZDZ provides four efficiency/resistance options (45%, 65%, 85%, 95%) in a compact mini-pleat format. It is particularly useful when the project needs a rigid 295 mm-deep filter and wants to balance retention against airflow resistance for dust, oil mist, and chemical fumes.

Why can two ZDZ filters with the same external size have different airflow ratings?

Because external dimensions do not define internal media pack geometry. Pleat count, pleat height, and spacing change available media area. YONGFAN’s source data lists both ZDZ-12-95 and ZDZ-25-95 at 595×595×295 mm, but at 1,200 m³/h and 2,500 m³/h respectively.

When is ZYG preferred?

ZYG is the rigid separator-box option featuring glass-fibre paper, aluminum-foil separators, and a galvanized-steel frame. It is preferred when a self-supporting glass-fibre pack is specified and operating conditions fall within the 80 °C maximum temperature / 80% RH limits.

Can I replace an F7 bag filter with an F7 V-bank filter?

Not from the grade label alone. Verify face dimensions, depth clearance (600 mm vs 295 mm), rated airflow, clean ΔP, final ΔP allowance, frame mounting interface, and test basis. A matching efficiency label does not guarantee a drop-in physical replacement.

Should I always use the highest medium-filter efficiency before a HEPA filter?

No. The optimal grade balances HEPA protection against available fan static pressure and annual energy consumption. Increasing medium efficiency from F7 to F9 reduces HEPA dust loading, but adds permanent static pressure to the fan system.

Are medium bag filters washable?

The YONGFAN ZF5(6) source specifically describes multiple-wash reuse. However, other bag, mini-pleat, and box filters should not automatically be treated as washable unless the selected product datasheet confirms it, and proper cleaning procedures must prevent media tear.

08 / Application Boundaries

Medium Filters Are Not Terminal HEPA Filters

Medium-efficiency filters are engineered to remove intermediate particle loads and protect downstream coils and final stages. Understanding their boundaries prevents costly misapplication.
Boundary 01 / Terminal Cleanliness

Not HEPA/ULPA Media

Medium filters do not achieve ISO cleanroom classifications on their own. Where sterile pharma or microelectronics cleanliness is required, selection must move to H13–U17 terminal filters.

Boundary 02 / Molecular Contamination

Do Not Remove VOCs or Gases

Even an F9 bag filter capturing 98% of sub-micron particles cannot adsorb molecular gases. Odors, H2S, SO2, and VOCs require dedicated activated-carbon or chemical filtration.

Boundary 03 / Mechanical Bypass

Higher Grade ≠ Bypass Immunity

A higher efficiency filter cannot compensate for poorly sealed holding frames. Gasket compression, clamping rigidity, and bank sealing remain vital to prevent bypass around media.

Boundary 04 / Complete Train

Staged System Budget

Size the medium stage as part of the total pressure and cleanliness train: Pre-filter → Medium filter → Final filter, ensuring the fan is sized for loaded system resistance.

09 / Engineering Handoff

Select the Right Medium-Efficiency Filter for Your AHU

You do not need to determine the exact part code alone. Send your bank dimensions, design airflow, allowable clean resistance, and downstream cleanliness targets — our application engineers will confirm the compliant family and duty point.

Bank Opening W × H × D (mm) Airflow Rating (m³/h or CFM) Target Grade: F5, F6, F7, F8, F9 / ePM Clean ΔP Budget (50–140 Pa) Bag (600 mm) vs Compact (295 mm) Downstream: Coil / HEPA Stage
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