Ventilation and clean air
Fine filtration of supply air — from ordinary ventilation to ISO 5 cleanrooms. G3, G4, M5/F5, F6, F7, F8, F9, ePM and HEPA: panels, pockets, V-bank, compact cells and final filters selected by airflow, ΔP, climate and required cleanliness.
Where it is used
From prefilter to final stage
The cascade is built so that coarse dust never overloads the higher-value final stage and drives it rapidly to terminal pressure drop.
The first stage: they protect expensive filters and heat exchangers from coarse dust. Synthetic fibre, corrugated board or metal frame, galvanised mesh. Initial ΔP 30–60 Pa, final 200–250 Pa.
- Changed 3–4 times more often than the next stage
- Saving here costs you more downstream
The main working stage of supply ventilation: large area in a shallow depth. Synthetic fibre, glass fibre for the higher grades; galvanised steel or plastic frame; 4–8 pockets, depth 360 / 600 mm.
- Without a prefilter the life drops several times over
- Sagging pockets mean lost area
Minimum depth at high efficiency — where there is no room for a pocket filter. Glass fibre or synthetic media, plastic or galvanised frame, moisture-resistant build; depth 292 / 400 mm.
- The standard for cleanroom supply air
- F7–F9 is mandatory ahead of HEPA
High area and stable geometry in a short depth. Fine final or pre-HEPA stage: pocket, V-bank or rigid cell.
- Efficiency report and fan energy are checked
- Space, moisture, ΔP and lifecycle cost decide
The final stage for cleanrooms, operating theatres and pharmaceutical production. Glass fibre, aluminium separators, gel or polyurethane seal; anodised aluminium or stainless steel frame. Mini-pleat, deep pleat with separators or compact V build; initial ΔP 120–250 Pa; scan test, DOP/PAO.
- Fitted only after F7–F9
- Every filter comes with a test certificate
- A damaged seal reduces the grade to nothing
ULPA — ultra-fine filtration for microelectronics and ISO 3–5 sterile zones: high-density glass fibre, separator-free build, gel seal, initial ΔP 200–350 Pa. Carbon filters remove odours and light organic compounds where mechanical filtration cannot help: granular or gas-specific impregnated carbon, bed depth 25–100 mm, service life 3–12 months.
- ULPA requires conditioned supply air; replacement only with re-validation of the zone
- The carbon is chosen for the specific gas; humidity above 70% cuts the capacity
Materials and versions
- Synthetic fibre — standard
- Glass fibre — HEPA / ULPA
- Aluminium separators
- Frame: galvanised steel, stainless steel, plastic
- Seal: polyurethane, gel
- Housings, frames, clamps and seals
Typical specification
| Parameter | Value |
|---|---|
| Classes | ISO 16890 / EN 779 / EN 1822 |
| HEPA efficiency | 99.95 – 99.995% @ 0.3 µm |
| Flow per section | 1,000 – 25,000 m³/h |
| Initial ΔP | 30 – 120 Pa |
| Final ΔP | 250 – 450 Pa |
| Operating temperature | up to 80 °C (standard) |
Temperature and humidity are confirmed by the specific filter datasheet. A media limit must not be applied to the complete cell: frame, sealant, separator and gasket may impose a lower rating.
Legacy labels are shown alongside test data
G3–F9 labels help identify existing replacements, while project selection uses test data to the applicable ISO 16890 edition, airflow and ΔP. There is no universal direct conversion between grades.
- Typical role
- Coarse prefiltration
- Construction
- Panel, cell or pocket
- Verify
- Dust holding, moisture and fire behaviour
Where it works and where it does not fit
- Supply ventilation and cleanrooms
- Final stage after coarse filtration
- Protection of equipment and product from dust
- Seasonal protection from pollen and smog
- High dust load without a prefilter — life drops several-fold
- Aggressive chemistry and acidic gases
- Above 80 °C for standard versions
- Humidity that condenses on the media
Data for replacement or new design
- 01Size
Width, height, depth, frame, pockets and gasket.
- 02Air
Flow, temperature, humidity and outdoor or recirculated duty.
- 03Requirement
Grade, test report, allowable ΔP, final purity and life.
- 04System
AHU model, fan, frames, number of stages and service access.
Frequently asked questions
Can F7 be directly replaced by ePM1?
There is no universal conversion. Compare the product test report, airflow, initial and terminal ΔP, dimensions and project requirement.
Is a pocket or V-bank filter better?
Pockets offer economical dust holding; V-bank cells provide high area and stable geometry in a compact depth. Space, moisture, ΔP and lifecycle cost decide.
Why does a filter collapse or tear?
Potential causes include excess flow, a blocked stage, a weak frame, wetting, wrong orientation or missing support. Inspect both aerodynamics and installation.
When is HEPA required?
When final cleanliness and process risk require a high-efficiency final stage. HEPA requires verified classification and installation leak-tightness control.
Can custom sizes be supplied?
Yes, after checking frame, interface, flow direction, required area and available pressure drop. An approved drawing is retained for repeat supply.
Filter types in 3D
Related pages
Why legacy grades cannot be mechanically converted to new ones and what a test report must show.
Open →Panel, pocket, V-bank or HEPASelecting a ventilation filter for AHUs and clean areas: grade cascade, dust holding, dimensions, airflow and allowable ΔP.
Open →Gas turbine air intake
3DStatic, pulse-cleaned and hybrid inlet systems for gas turbines: prefilters, coalescers, V-cell cassettes and cartridges — protecting the compressor from dust, moisture and salt aerosol.
Open →We map every stage in your ventilation system
We record dimensions, grades, airflow, ΔP and the replacement schedule, then select original or technically equivalent filters for Central Asia and the CIS. An engineer replies with a selection and specification within one working day.