Are the filters resistant to humidity?

Yes. The filters are designed to operate in environments with humidity levels of up to 100% RH.

What temperatures can the filters withstand?

Our rigid filters can operate at temperatures up to 80°C.

Why choose a plastic frame rather than a metal frame?

Plastic frames are lightweight, corrosion-resistant and extremely durable. They provide excellent structural stability and eliminate the risk of frame collapse.

Are standard sizes available?

Yes. Maxi Filtration holds a range of standard sizes in stock for fast delivery, with bespoke sizes available to order.

Can you manufacture custom sizes?

Yes. We regularly produce non-standard and bespoke rigid filters to suit specific AHUs, HVAC installations and filtration requirements.

How often should rigid filters be replaced?

Filter life depends on airflow, operating conditions and contaminant levels. Regular monitoring of pressure drop is recommended to determine the optimal replacement schedule.

Do rigid filters help improve indoor air quality?

Yes. Their high-efficiency filter media effectively captures fine airborne particles, helping maintain cleaner indoor air and protecting sensitive equipment and processes.

Compact & rigid filters

M6 – F9 rigid filters

A V-shaped minipleat rigid filter in a moulded plastic frame, used as a secondary filter, as a replacement for the standard bag filter, or as fine pre-filtration for HEPA filters.

M6 – F9
ePM10 65% – ePM1 80%
Also E10 – H14

Grey moulded plastic M6 – F9 rigid filter with white V-shaped minipleat media banks

Filter grade

M6 – F9 / ePM10 65% – ePM1 80%

Technical specificationM6 – F9 rigid

M6 – F9 rigid filters technical specification
EN 779	M6 – F9 (also E10 – H14)
ISO 16890	ePM10 65% – ePM1 80%
Filter role	Secondary filtration, bag filter replacement, HEPA pre-filter
Media	Microfine glass or synthetic fibre minipleat
Frame	Moulded plastic, V-shape
Header	20mm or 25mm
Depth	292mm
Max operating temperature	Up to 80°C
Humidity resistance	Up to 100% RH
Disposal	Incinerable
Availability	Three standard sizes, stocked for next-day delivery
Testing	Media tested to ISO 16890 and EN 779:2012

Standard sizes

Common sizes

Rigid filters are made in three standard sizes. Nominal imperial sizes with their actual metric dimensions (height × width × depth).

M6 – F9 rigid filters common sizes
Nominal (inches)	Actual (mm)
24 × 24 × 12	592 × 592 × 292
24 × 20 × 12	592 × 492 × 292
24 × 12 × 12	592 × 289 × 292

Efficiency

Grades available

Each grade shown to ISO 16890 (EN 779:2012). Also available in E10 – H14.

EN 779:2012 grades and their ISO 16890 equivalents
EN 779:2012	ISO 16890
M6	ePM10 65%
F7	ePM2.5 70%
F8	ePM1 60%
F9	ePM1 80%

Product features

Construction and performance

For use as a secondary filter, as a replacement for the standard bag filter, or as fine pre-filtration for HEPA products, especially in hospitals, offices, computer centres, pharmaceutical, microelectronics and the food industry.
Constructed with high capacity, microfine glass or synthetic fibre minipleat, bonded into a moulded plastic frame engineered for maximum strength and optimum airflow.
Available in grades M6 to F9, and also E10 to H14.
Made in three standard sizes, stocked for next-day delivery.
The all plastic frame makes rigid filters long lasting and very efficient.
The compact configuration can retrofit bag filters and fits existing filter housings with no modification.
Longer life and reduced energy consumption.
V-shape design creates a low resistance to airflow.
Available with a 20mm or 25mm header.
Humidity resistant up to 100% RH.
Temperature resistant up to 80°C.
Incinerable and environmentally friendly.
Media tested to ISO 16890 and EN 779:2012.

Key benefits

The V configuration creates a larger surface area, giving fine filtration with an extremely high dust holding capacity and consistently high indoor air quality.
The V design is energy efficient, and the high-performance media increases service life while reducing filter changes and costs.
The plastic frame is totally stable and will not collapse during downtime.

Typical applications

Hospitals
Offices
Computer centres
Pharmaceutical
Microelectronics
Food industry
HEPA pre-filtration

Talk to the Maxi team

Interested in m6 – f9 rigid filters?

Make an enquiry

Compare the range

How M6 – F9 rigid compares with other compact filters

Compact & rigid filters types compared
Specification	M6 – F9 rigid	M5 – F9 compact	High temperature
EN 779	M6 – F9 (also E10 – H14)	M5 – F9	M6 – F7
ISO 16890	ePM10 65% – ePM1 80%	ePM10 60% – ePM1 80%	ePM10 70% (M6), ePM1 55% (F7)
Media	Microfine glass or synthetic fibre minipleat	Microfine glass fibre or synthetic minipleat	Glass fibre paper with aluminium corrugated separators and safety edges
Frame	Moulded plastic, V-shape	Metal, plastic or card cased	Galvanised steel, warp resistant
Header	20mm or 25mm	With or without a header	22mm header
Max temperature	Up to 80°C	Standard HVAC	Up to 230°C
Best for	Secondary filtration, bag filter replacement, HEPA pre-filter	High airflow in limited space	Kitchen extract, process and paint spray

FAQs