Air filtration media — Which of the following materials are used as filter media in air filtration systems for bioprocess or cleanroom applications?

Introduction:
Air filtration in bioprocessing and clean facilities uses a range of media designed to remove particulates, aerosols, and sometimes volatile contaminants or odors. Understanding common filter media helps in selecting prefilters, HEPA stages, and specialty cartridges for odor or VOC control.

Given Data / Assumptions:

• Generic HVAC/cleanroom and process-air contexts.
• Media considered: glass wool, glass fibre, activated carbon (Norite).
• Objective: particulate removal and/or adsorption of gaseous species.

Concept / Approach:
Glass wool and glass fibre mats form depth media widely used in prefilters and HEPA/ULPA filters to capture particles by interception, impaction, and diffusion. Norite is a trade name for activated carbon, which provides a high surface area for adsorption of organic vapors and odors; while not a particulate filter per se, it is commonly installed as a companion stage in air handling to improve air quality.

Step-by-Step Solution:
Recognize that glass wool/fibre are standard fibrous media for particulate removal (up to HEPA grades for glass microfibers).Recognize that activated carbon (Norite) is frequently used as an adsorption stage for gases and odors.Since all listed materials are used in air filtration systems, select “All of the above”.

Verification / Alternative check:
Typical air-handling units show trains like prefilter (fibrous) → HEPA (glass microfibre) → carbon bed for VOC control.

Why Other Options Are Wrong:

• Each individual choice is incomplete; modern systems often combine them.
• “None of the above” is incorrect because these are standard media.

Common Pitfalls:
Confusing particle filtration with gas adsorption; expecting a single medium to handle both particulates and VOCs optimally.

Final Answer:
All of the above