When it's time to reorder exhaust filters, you hit a fork in the road: kraft-paper Andreae accordions, spun fiberglass, or pocket/bag filters. All three sit on the same shelf, all three claim to keep you compliant, and the price spread between them is real. So which belongs in your booth? The honest answer is that it depends on how you spray, how much overspray you generate, and how you'd rather spend your time and money — not on which one is "best." Here's the head-to-head.
First, the thing all three share: 98% capture
Before we compare, clear up the compliance question. Specced and installed correctly, all three of these medias can meet the federal NESHAP 6H requirement to capture at least 98% of paint overspray by weight. None of them is "more compliant" than the others. So your decision isn't about passing an audit — it's about total cost of ownership: purchase price, how much overspray each holds before it loads up, how messy it is to handle, and how long it lasts. (Compliance guidance here is general, not legal advice — confirm with your state or local air authority via our compliance hub.)
Andreae accordion (kraft paper)
The Andreae filter is a folded kraft-paper accordion with staggered slots on alternating faces. Incoming air is forced to change direction repeatedly as it snakes through the pleats; the heavier overspray particles can't make the turns, so they impact and stick to the paper walls. As the filter loads, the accordion progressively collapses, exposing fresh media and keeping pressure drop stable across a long service life.
- Strengths: very high overspray-holding capacity, stable airflow as it loads, minimal fiber shedding, easy visual load-check.
- Trade-offs: higher upfront cost per pad than raw fiberglass; you need to match the right AF pleat count to your paint volume.
Choosing the pleat count is the whole game with these — our Andreae AF number guide walks through matching AF150, AF300, and the rest to your booth. Shop the Andreae exhaust filter collection when you know your size.
Fiberglass (spun-glass rolls and pads)
Fiberglass is the workhorse budget media — tackified spun glass with a progressive-density structure that's coarse on the air-entry face and dense on the exit. Overspray loads through the depth of the media rather than just on the surface. It's the lowest purchase price of the three and ships as cut pads or continuous fiberglass rolls you size yourself. For a closer two-way look at synthetic versus glass media, see polyester vs. fiberglass exhaust filters, and for the full range of roll medias and how they differ, our guide to the different types of air filter roll.
- Strengths: lowest upfront cost, widely available, easy to cut to any frame.
- Trade-offs: lower holding capacity than Andreae, so more frequent changes on high-volume booths; glass fibers make it messier to handle and dispose of; not reusable.
Pocket / bag filters
Pocket (bag) filters use extended-surface pockets to pack a large amount of media into a compact frame. That surface area gives them high dust-holding capacity and a long service life, which is why they're often run as a second-stage or final exhaust filter behind a primary that catches the bulk of the overspray. Browse pocket/bag filters and exhaust filter bags for stack configurations. If you're specifically weighing pockets against rigid panel filters, our pocket/bag vs. panel exhaust comparison breaks that choice down.
- Strengths: highest surface area and dust-holding, long service life, excellent as a polishing/second stage.
- Trade-offs: highest upfront cost, needs the frame/track depth to accommodate the pockets, usually paired with a primary filter rather than run alone.
Head-to-head comparison
| Attribute | Andreae accordion | Fiberglass | Pocket / bag |
|---|---|---|---|
| Upfront cost | Moderate | Lowest | Highest |
| Overspray-holding capacity | High | Moderate | Very high (surface area) |
| Cleanliness / mess to handle | Clean (paper, low shed) | Messiest (glass fibers) | Clean (synthetic) |
| Airflow stability as it loads | Excellent (progressive collapse) | Good | Good |
| Typical service life | Long | Shorter on high volume | Longest (as 2nd stage) |
| Meets 98% when specced right? | Yes | Yes | Yes |
| Best use | High-volume primary exhaust | Budget primary, lower volume | Second-stage / final polishing |
How to choose for your booth
- High paint volume, want fewer changeouts: Andreae accordion — the holding capacity and stable airflow pay back the higher unit cost in labor and downtime.
- Lower volume or tight budget: fiberglass primary — cheapest to buy, just plan on changing it more often and handling the glass mess.
- Chasing the cleanest exhaust or protecting a stack: add a pocket/bag second stage behind a primary.
Whatever you pick, change it on load — not on the calendar. See when to replace paint booth filters and our overview of how paint booth exhaust filters work to dial in your schedule.
Frequently asked questions
Which exhaust filter lasts the longest?
By holding capacity, pocket/bag filters run as a second stage last the longest, followed by Andreae accordions as a primary. Fiberglass is the shortest-lived on high-volume work. But service life always depends on how much overspray you generate — change on measured load, not a fixed date.
Is Andreae worth the extra cost over fiberglass?
On a high-volume booth, usually yes. The higher holding capacity means fewer changeouts, less downtime, and a cleaner, glass-free filter to handle. On a low-volume booth, fiberglass's low price can win on total cost.
Do all three meet NESHAP 6H?
Yes, when you select the correct grade and size for your booth and airflow. The 98%-by-weight capture requirement is about specifying and installing the right filter, not about which media family you choose. This is general guidance, not legal advice — confirm with your air authority.
Can I run fiberglass and a pocket filter together?
Yes — a common setup is a primary (fiberglass or Andreae) to catch the bulk of overspray and a pocket/bag second stage to polish the exhaust and protect your stack and fan.
Get the right exhaust media the first time
Still weighing it up? Browse the full paint booth exhaust filter collection to compare Andreae, fiberglass, and pocket options side by side, or use our Find My Filter tool. Tell us your booth, your paint volume, and your current changeout headaches — we'll match you to the media that lowers your real cost per finish.