Selection Guide: How to Choose the Right Cleanroom Air Filter

Choosing the right air filter for your cleanroom is a balance of required air cleanliness, system design and operating cost. This guide walks through the key decisions.

Step 1: Determine the Required Filter Class

Your cleanroom classification (ISO 14644-1) sets the minimum filter efficiency. As a rule of thumb:

  • ISO Class 5 (100): H13-H14 HEPA at the terminal, H13 in the AHU
  • ISO Class 4: H14 HEPA, often ULPA for critical zones
  • ISO Class 1-3: ULPA U15-U17
  • ISO Class 6-8: H13 HEPA at terminal, F7-F9 fine filters in the AHU

Step 2: Check the Filter Efficiency Standard

All Onecleans HEPA/ULPA filters are tested to EN 1822 (MPPS method). Confirm whether your project references EN 1822, ISO 29463, or a national standard (e.g., GB/T 13554 for China).

Step 3: Define Dimensions & Airflow

Filters are available in standard sizes (e.g., 484×484×90 mm, 610×610×150 mm, 610×610×292 mm) and custom sizes. Provide your duct or housing dimensions and design airflow, and we will confirm pressure drop and filter count.

Step 4: Choose Frame & Sealing Method

  • Frame material: galvanized steel, aluminium, stainless steel (corrosive or high-temperature areas)
  • Sealing: EVA/PU gasket for standard housings; gel seal (liquid gasket) with knife-edge frame for critical installations requiring guaranteed leak-free sealing

Step 5: Consider Operating Conditions

  • High temperature: 250°C / 300°C / 350°C filter series for ovens and spray booths
  • High humidity: waterproof media and corrosion-resistant frames
  • Prefilter stage: always protect the final filter with G4-F9 prefilters to extend service life

Step 6: Request a Specification

Send us the following information and we will confirm the right product within 24 hours:

  • Application and cleanroom class
  • Dimensions (W×H×D)
  • Design airflow (m³/h)
  • Required efficiency class
  • Temperature / humidity conditions

Request a quote or contact our engineers.