Medical-Grade Air Filter Application and Selection Guide

The Ultimate Protection Solution for Hospitals, Operating Rooms, ICUs, and Clean Medical Environments

In 2026—an era shaped by the post-pandemic landscape and accelerating population aging—medical-grade air filters have become indispensable core protection systems for hospitals, clinics, long-term care facilities, pharmaceutical plants, and biological laboratories.

These filtration systems not only effectively block bacteria, viruses, fungal spores, and airborne particulate matter, but also play a critical role in:

Infection control
Patient safety
Occupational health of healthcare personnel
Compliance with GMP, ISO 14644, hospital accreditation standards, and Ministry of Health regulations

This article provides a comprehensive analysis of medical-grade air filter types, core international standards, hospital-area application scenarios, key selection criteria, and why high-efficiency HEPA/ULPA filters have become an essential public standard for healthcare institutions.

Recommended for:
Hospital engineering departments, infection control committees, cleanroom facility managers, and medical equipment procurement professionals.

Why Must Healthcare Environments Use Professional Medical-Grade Air Filters?

Air contaminants in medical environments originate from complex sources, including:

Surgical smoke and aerosol-generating procedures (AGPs)
Respiratory viruses (e.g., influenza, COVID-19 variants, tuberculosis)
Fungal spores, dust mites, and allergens
Bacteria (e.g., Staphylococcus aureus, Pseudomonas aeruginosa)
Volatile organic compounds (VOCs) and residual chemical disinfectants

Without effective control, these contaminants may result in:

Increased hospital-acquired infection (HAI) rates in operating rooms and ICUs
Elevated infection risks for immunocompromised patients (e.g., chemotherapy, transplant recipients)
Occupational exposure and long-term health hazards for healthcare workers
Non-compliance with Ministry of Health Infection Control Regulations, ASHRAE 170, EN 1822, ISO 14644, and other standards

Types of Medical-Grade Air Filters and International Standards

Medical air filters are classified based on filtration efficiency and target particle size. Common standards include:

EN 1822 / ISO 29463

HEPA H13: ≥99.95% at MPPS
HEPA H14: ≥99.995% at MPPS
ULPA U15–U17: ≥99.999% at 0.1–0.2 μm

ASHRAE 52.2

MERV 14–16: Used for pre-filtration in general healthcare areas

ISO 14644-1

Cleanroom classifications (ISO 5–8 commonly used in sterile medical zones)

ASHRAE Standard 170

Ventilation requirements for healthcare facilities
Requires HEPA terminal filtration in operating rooms and Protective Environment (PE) rooms

Overview of Common Medical-Grade Filters

1. Pre-Filters / Medium-Efficiency Filters

(MERV 7–13 / G4–F9)

Capture large particles (>1–10 μm) such as hair, fibers, and dust.
Used as upstream protection to extend HEPA lifespan.
Suitable for general wards, outpatient areas, and administrative HVAC systems.

2. HEPA Filters (H13 / H14)

Efficiency ≥99.95–99.995% at MPPS (typically 0.1–0.3 μm).
Mainstream choice for healthcare environments.

Effectively removes:

Bacteria
Virus carriers
Pollen
Fungal spores

Common designs include separatorless and mini-pleat structures for lower pressure drop and lightweight construction.

3. ULPA Filters (U15)

Efficiency ≥99.999% at 0.1–0.2 μm.

Used in:

Aseptic pharmaceutical filling lines
Cell therapy rooms
Gene therapy laboratories
High-end sterile medical device packaging areas

4. Chemical Filters

Adsorb:

VOCs
Formaldehyde
Anesthetic gases
Disinfectant residues (e.g., glutaraldehyde, hydrogen peroxide)

Often combined with HEPA filters in operating rooms and chemotherapy preparation areas.

5. FFU (Fan Filter Unit)

Integrated fan + HEPA/ULPA module.
Installed in ceilings to provide localized laminar airflow.

Standard equipment for:

Operating rooms
Clean preparation rooms
Biosafety cabinets

Recommended Filter Applications by Hospital Area

Area	Cleanliness Level (ISO)	Recommended Filter Grade	Key Contaminant Control	Typical Equipment
General Ward / Outpatient	ISO 8 or below	MERV 13–14 + H13	PM2.5, allergens, respiratory droplets	Central AHU
Protective Environment (PE) Room	ISO 7	H13–H14 HEPA terminal	Mold & bacteria protection	Terminal HEPA box / FFU
ICU / Isolation Room	ISO 7–8	H13–H14 + antimicrobial coating	Viral aerosols, MDR bacteria	FFU / dedicated air handler
Operating Room (Class A/B)	ISO 5–7	H14 HEPA + laminar flow	Surgical smoke, aerosols, bacteria	Laminar flow canopy / FFU array
Sterile Pharmacy / Compounding	ISO 5–7	H14 / ULPA	Particulates & cross-contamination	BSC / clean bench
Cell / Gene Therapy Lab	ISO 4–5	ULPA U15+	Nano-scale contaminants, viral vectors	High-clean FFU system

Five Practical Considerations for Selecting Medical-Grade Air Filters

1. Cleanliness & Regulatory Requirements

Confirm ISO classification and ASHRAE compliance requirements for the specific area.

2. Filtration Efficiency & MPPS Testing

Prioritize filters certified under EN 1822 MPPS testing.
Avoid products labeled only as “99.97% @ 0.3 μm,” which reflect outdated testing standards.

3. Pressure Drop & Energy Efficiency

Healthcare HVAC systems operate 24/7.
Low initial pressure drop (<250 Pa) significantly reduces fan energy consumption and operational costs.

4. Dust-Holding Capacity & Replacement Cycle

High-capacity designs (deep-pleat or V-bank) extend service life, reduce downtime, and minimize infection risk during maintenance.

5. Certification & Integrity Testing

Factory DOP/PAO scan test reports required
On-site integrity testing (DOP or DEHS challenge test) must be conducted after installation to ensure zero leakage