In healthcare environments, maintaining clean, contaminant-free air is not just a matter of comfort – it’s a matter of safety. From patient rooms to surgical suites, the quality of air directly impacts health outcomes and infection control. One of the most effective ways to ensure air purity is by using the right type of air filter in your HVAC systems.

Here’s a breakdown of the most common types of air filters used in healthcare facilities, what they’re made of and why they matter.

Fiberglass Filters

Best For: Basic pre-filtration and low-traffic areas
Features:

  • Made from spun glass fibers
  • Disposable and inexpensive
  • Typically rated MERV 1-4
  • Captures large particles like dust and lint

Why They’re Used:
While not suitable for critical care areas, fiberglass filters are often used as pre-filters to catch larger debris, helping extend the life of higher-efficiency filters downstream.

Use in Healthcare: Commonly used as pre-filters to trap large particles before the air reaches more efficient filters. Not recommended for critical care areas.

Pleated Filters (MERV 8 and Above)

Best For: General air filtration in administrative or non-critical care spaces
Features:

  • Made of cotton or polyester media folded into pleats for greater surface area
  • Typically rated MERV 6–13
  • Captures particles like pollen, mold spores and dust mites

Why They’re Used:
MERV 8 pleated filters strike a good balance between performance and airflow efficiency. They’re commonly used in waiting rooms, offices and storage areas – not in surgical or sterile environments but still within the facility.

Use in Healthcare: Ideal for waiting rooms, administrative offices and common areas. Not sufficient for operating rooms or isolation rooms.

Bag Filters (Pocket Filters)

Best For: Medium- to high-efficiency filtration in large HVAC systems
Features:

  • Made of synthetic media arranged in long pockets or “bags”
  • High dust-holding capacity and airflow efficiency
  • Rated MERV 9–15 depending on material and depth

Why They’re Used:
Bag filters are often used as a secondary stage in multi-filter systems. They are especially beneficial in high-volume air handling units due to their extended surface area and ability to trap smaller particles over long periods.

Use in Healthcare: Frequently used as secondary filters in a multi-stage filtration system. Suitable for patient care areas and mechanical rooms.

HEPA Filters (High-Efficiency Particulate Air)

Best For: Surgical suites, isolation rooms, cleanrooms and laboratories
Features:

  • Removes at least 99.97% of particles ≥0.3 microns in size
  • Dense filter media (often fiberglass or synthetic polymer)
  • Requires powerful fans to move air due to high resistance

Why They’re Used:
HEPA filters are critical in infection control and airborne pathogen containment. These filters are standard in operating rooms, oncology wards and areas where immunocompromised patients are treated. Their superior filtration performance makes them essential in any high-risk environment.

Use in Healthcare: Essential for infection control in sensitive environments like operating rooms, cleanrooms and oncology departments.

ULPA Filters (Ultra-Low Penetration Air) – Rare Use

Best For: Cleanrooms with the strictest air purity standards
Features:

  • Removes 99.999% of particles ≥0.12 microns
  • Even more efficient than HEPA
  • Rarely used outside of specialized research or pharmaceutical settings

Why They’re Used:
ULPA filters are usually found in advanced biosafety labs or manufacturing environments – not typical healthcare facilities – but may be used in specialized applications.

Use in Healthcare: Rarely used outside of specialized labs or pharmaceutical manufacturing. May be found in some advanced biosafety applications.

Choosing the Right Filter Mix

Most healthcare HVAC systems don’t rely on just one type of filter. Instead, they use a multi-stage filtration system, combining a pre-filter (fiberglass or pleated), a secondary filter (bag), and a final stage (HEPA) where needed. This layered approach improves air quality while protecting expensive HEPA filters from premature clogging.

Maintenance Matters

Choosing the right filter is only half the battle. Regular inspections and replacements are key to ensuring continued air quality and compliance with healthcare standards.

Air filters in healthcare settings do more than just remove dust – they help control infection, safeguard patient health and ensure regulatory compliance. Regular filter replacement and inspection are just as important as using the correct filter type.

At Tyger River HVAC & Fire, we support healthcare facilities across the Carolinas with expert HVAC maintenance, including filter replacement schedules that keep systems running efficiently and safely.