New Air Purifiers, a $3.5M School Deal & Scary AQI in Delhi
Welcome to the Air Purification Education Month in Review for November 2025.
A lot happened in the air purifier and air quality world last month:
1. Several brands released new air purification solutions – including one particularly interesting smart ventilation product.
2. An air purifier manufacturer landed a £2.7 million (~$3.5 million) contract with more than 200 schools in London.
3. A new study identified air pollution as responsible for 8% of all cardiovascular deaths in the European Union.
4. Air pollution in one major city became so bad that schools closed and doctors told people to leave the city if possible.
Let’s break it all down, starting with the new hardware.
1. New Air Purifiers & Designs Launched in November 2025
Alen 25i: Compact Bedroom HEPA Solution
In November, Alen released a small room air purifier called the 25i:
Key specs:
- Approx. 16.8″ tall × 11″ wide × 7.3″ deep
- Weight: about 8 pounds
- Coverage: up to 200 sq. ft. at 4 ACH with 8 ft. ceilings
- Noise: around 40 dB on high speed (quiet side of the spectrum for a small HEPA unit)
- Filter options: 3 different filter types depending on how much carbon you want in the solution
- Pricing: $179 MSRP – currently listed around $161.10 on sale at the time of this post.
For people who need a small, quiet, particle filtration solution for a bedroom or dorm room, the 25i could be a reasonable option in the compact category.
I would currently consider the Alen 25i to be a Tier 2 particle filtration solution (CLICK HERE for my list of BEST Asthma, Allergy and Particle filtration Air Purifiers).
👉 Link to the Alen 25i product page
Rabbit Air releases New Peanuts Designs
Rabbit Air didn’t launch a new unit in November, but they did expand their design options with new Peanuts-themed front panels.
Rabbit Air is celebrating 75 years of Peanuts with two new designs:
- “Hanging Around” – featuring Snoopy and Woodstock hanging out together.
- “Good Vibes” – “Peanuts Social Club – since 1950.”
From a purely aesthetic standpoint, I much prefer the “Hanging Around” design with Snoopy and Woodstock. And out of all their Peanuts designs – I personally prefer the “Full Heart” one with Snoopy hugging a big heart. But that’s just my preference.
Price range: Rabbit Air units with Peanuts designs generally land in the $620–$770 range, depending on the base model.
👉 Link to the Rabbit Air Peanuts editions
Blueair Pro Purify + Humidify: 2-in-1 HEPA + Humidifier “Birdbath”
Next up, Blueair introduced a 2-in-1 solution called the Blueair Pro Purify + Humidify in November.
My initial thoughts are, it looks kinda like an air purifier with a birdbath on top.
It is a HEPA-based purifier on the bottom and an integrated humidifier on top.
Key details:
- Marketed benefits: cleaner air plus added humidity to help with dry skin, dryness-related irritation, and comfort
- Dimensions: 12.5″ diameter × 26.4″ tall
- Weight: about 18.5 pounds
- Water tank capacity: ~1 gallon
- Coverage: up to ~400 sq. ft. at 4 ACH (8 ft. ceilings)
- Price: $499.99
👉 Link to the Blueair Pro Purify + Humidify
ClearChang Rebreeze: Smart Window-Mounted Air Purifier & Ventilation System
One of the most interesting November highlights came from CES 2025 in Las Vegas: a Korean company called ClearChang introduced a product named Rebreeze.
This isn’t just a standard room air purifier. It’s more like a smart, window-integrated ventilation and filtration system.
What Rebreeze does:
- Installs into the window frame – more like a built-in appliance than a portable box
- Draws in outdoor air and filters it, while exhausting indoor air (including CO₂, VOCs, and fine dust)
- Uses nano-fiber filtration – ClearChang claims it can even capture some ultrafine particles
- Includes IoT + AI-driven monitoring via a mobile app
- Continuously tracks metrics like:
- PM2.5
- CO₂ levels
- Humidity
- Automatically adjusts airflow and ventilation based on real-time indoor + outdoor conditions
- Future models are planned to add AI analytics, climate-adaptive control, and smart home integration
Why this matters:
- CO₂ cannot be removed by HEPA or carbon filters. If CO₂ is high, you need ventilation, not just filtration.
- Simply “opening a window” often means bringing pollen, pollution, and outdoor particles into your home.
- A unit like Rebreeze aims to solve both problems at once: ventilation with filtration.
ClearChang has been around since 2019, building advanced carbon fiber screens and ventilation systems, so this isn’t a brand-new company without any history. The product looks promising.
Pricing hasn’t been clearly listed yet, but given the tech and integration, it likely won’t be cheap. That said, it’s definitely a company and product line worth watching.
👉 Link to ClearChang and Rebreeze
🎥 Watch the Full November 2025 Month-in-Review Video:
2. Air Purifier Manufacturer Wins £2.7M (~$3.57M) HEPA Contract with 200+ London Schools
Now to one of the bigger business stories of the month.
The Mayor of London announced a £2.7 million investment in air quality filters for schools, which translates to roughly $3,573,450 USD. That’s a lot of money—and a lot of HEPA filters.
The question is: Which air purifier brand won this contract?
- IQAir? No.
- Austin Air? No.
- Camfil or Blueair? Nope.
The winner was Smart Air.
Smart Air Blast & Mini Blast Chosen for Classrooms
Smart Air Mini Blast – currently around $667 (US pricing)
Smart Air Blast – currently around $1,019 (US pricing)
Both are HEPA-based air purifiers, designed with a lot of airflow.
London Classroom Testing: HEPA vs. DIY MERV 13
According to the City Hall-commissioned research:
“PM2.5 levels in classrooms with HEPA filters were between 27% and 68% lower compared to those without.”
The tests included:
- Smart Air HEPA units (Blast/Mini Blast)
- DIY MERV 13 “CR Box” type solution (Corsi-Rosenthal box style)
In these tests, the Smart Air HEPA purifiers outperformed the DIY MERV 13 CR Box in terms of reducing PM2.5 concentrations in classrooms.
That’s a direct challenge to some of the more aggressive claims out there that:
- MERV 13 filters “destroy HEPA in real-world performance”
- “CADR is the only metric that matters“
For example, one peer reviewed study, conducted by Richard Corsi (who puts the “C” in CR Box) claims that a DIY CR box on low speed achieves around 600 CFM CADR, beating commercial HEPA units on maximum speed. If CADR were truly the only variable that mattered, the DIY CR boxes should have filtered better in the London study.
Yet:
- Smart Air Blast CADRs were in the ~437 CFM (Mini Blast) and ~559 CFM (Blast) range—lower than the claimed 600 CFM CADR CR Box number, on low speed.
- And still, the Smart Air HEPA units performed better in the classroom PM2.5 reduction tests.
What This Tells Us About MERV 13 vs. HEPA
This doesn’t mean MERV 13 solutions are “not useful”. I currently think that they:
- Can be quiet and energy efficient when paired with PC fans.
- Can be a decent solution for certain applications/needs, especially for larger sized particles.
However, the London study is another data point suggesting:
- Real-world performance is more complex than just CADR and filter ratings.
- Claims like “MERV 13 solutions will ALWAYS filter better than HEPA solutions at ALL particle sizes in ALL situations” are probably over-simplifications.
- Design, airflow patterns, leakage, mixing, placement, and room dynamics all matter.
I oftentimes say, “No single test will tell us everything about an air purifier’s performance.” So, we must always be openminded when presented with filtration testing results from various sources.
Either way, the biggest winners here are the students, teachers, and staff who will now be breathing cleaner air in those London classrooms.
👉 Link to the London schools article
3. EU Study: Air Pollution Causes 8% of All Cardiovascular Deaths
Next, let’s look at an important health study.
An article titled “One in five EU heart deaths linked to environmental hazards” highlights just how damaging air pollution is to cardiovascular health.
Key findings:
- Air pollution is identified as the most significant environmental risk to cardiovascular health in the EU.
- It accounts for about 8% of all cardiovascular deaths.
- PM2.5 alone is estimated to cause:
- Over 130,000 deaths per year from ischemic heart disease and stroke, and
- More than one million years of life lost annually in the EU.
- Second-hand smoke, another form of air pollution, is linked to about 2% of cardiovascular deaths.
- The report also warns that emissions from e-cigarettes may pose similar long-term risks, although the evidence base is still developing.
The takeaway:
- Air pollution is not just an “inconvenience” or a “smell” problem. It’s a major cardiovascular risk factor on the same playing field as some of the classic lifestyle risks.
👉 Link to the EU heart-health article
4. Delhi’s November 2025 Air Pollution Crisis: Schools Closed & “Leave If You Can”
In November, air quality in New Delhi, India reached truly alarming levels.
A CBS News article titled “Air pollution in Indian capital Delhi closes schools, draws protests and a warning for the sick to escape” outlined the situation.
Highlights:
- Authorities told elementary schools to move classes online.
- Construction was banned and people were urged to work from home.
- Delhi’s average AQI hit 425, which falls into the “severe” category.
- AQI between 400–450 typically triggers emergency measures under the government’s graded response plan.
- For the first time, the toxic air prompted public protests at India Gate, with citizens demanding cleaner air.
- People with health issues were advised to leave the city if possible.
Some additional context:
- Air quality in Delhi often deteriorates around this time due to a mix of farm waste burning, emissions, and seasonal weather patterns.
- One doctor made this horrific statement:
- “We have no non-smokers in India. Everybody living in India is a smoker.”
- A chest surgeon, Dr. Kumar, bluntly stated:
- Just breathing in Delhi at these AQI levels was equivalent to smoking 25 cigarettes a day. Which is absolutely CRAZY!
The Lancet’s Countdown on Health and Climate Change 2025 report added another grim statistic:
- India recorded around 1.72 million deaths from outdoor air pollution in 2022, a 38% increase since 2010.
At the time of this post, Delhi’s AQI had dropped to around 227 – still “Very Unhealthy”, but an improvement over 425. Hopefully those levels trend downward significantly and stay down.
If you missed last month’s recap, please check out:
October 2025 Air Purifier Industry & Air Quality Update: AirDoctor 4000, Airpura T400, New Studies on Air Pollution
*Air Purification Education is supported by readers and viewers. When you buy with our links or coupon codes we may earn a commission that does not affect the price of your purchase – We appreciate your support!
Frequently Asked Questions (FAQs)
1. What is the Alen 25i best used for?
The Alen A25i is best suited for small rooms like bedrooms, dorm rooms, and nurseries, where it can deliver around 4 ACH in up to ~200 sq. ft. with relatively quiet operation. It’s a compact HEPA-based option for people who mainly need particle filtration in a small space.
2. What is the ClearChang Rebreeze and how is it different from a normal air purifier?
ClearChang Rebreeze is a window-integrated air purifier and ventilation system that simultaneously brings in filtered outdoor air and exhausts indoor air. Unlike a typical portable purifier, it targets both particle pollution and CO₂ buildup by combining ventilation + filtration + smart sensors in one system.
3. Why is controlling CO₂ important if I already have a HEPA air purifier?
HEPA filters can’t remove CO₂, because CO₂ is a gas that passes through standard filter media. High indoor CO₂ can cause fatigue, headaches, and reduced cognitive performance, so you need ventilation or a system like Rebreeze to bring in fresher air while still filtering particles.
4. How did the Smart Air Blast units perform compared to DIY MERV 13 CR Boxes?
In the London classroom tests, Smart Air’s HEPA Blast units reduced PM2.5 more effectively than DIY MERV 13 Corsi-Rosenthal boxes, even though the CR Boxes had comparable or higher claimed CADR. This shows that real-world performance depends on more than just CADR and filter rating on paper.
5. Are DIY MERV 13 CR Boxes always better than HEPA air purifiers?
No, DIY MERV 13 CR Boxes are not always better than HEPA air purifiers in real-world use. They can be cost-effective and useful in certain situations, but the London study suggests that well-designed HEPA units can outperform them in classrooms, so context, design, and room dynamics all matter.
6. What does the EU study say about air pollution and heart disease?
The EU study cited in the article reports that air pollution accounts for about 8% of all cardiovascular deaths in the European Union. PM2.5 exposure alone is estimated to cause over 130,000 deaths per year from ischaemic heart disease and stroke, along with more than one million years of life lost annually.
7. How dangerous was the air quality in New Delhi in November 2025?
In November 2025, New Delhi’s AQI climbed to around 425, which falls in the “severe” category. Authorities closed schools, banned construction, and urged people with health issues to leave the city if possible, with one doctor comparing living there to smoking 25 cigarettes a day.
8. How many deaths in India are linked to outdoor air pollution?
According to the Lancet “Countdown on Health and Climate Change 2025” report, outdoor air pollution was linked to around 1.72 million deaths in India in 2022, representing a 38% increase since 2010. This underscores that air pollution is a major public health crisis, not just an inconvenience.
9. What is PM2.5 and why does it matter for air purifiers?
PM2.5 refers to airborne particles with a diameter of 2.5 microns or smaller, which are small enough to penetrate deep into the lungs and even enter the bloodstream. Because PM2.5 is strongly linked to heart disease, stroke, and lung problems, a good air purifier should be able to meaningfully reduce PM2.5 levels in your space.
10. Where can I find reliable air-purifier rankings and discount codes?
You can view updated air-purifier rankings and use the Airpura discount code DZAIR10 for 10% off at Airpura.com via Air Purification Education. You can use AllerAir discount code DZAIR15 for 15% off at AllerAir.com. And you can use Clean Air Kits discount code DZAIR5 for 5% off at CleanAirKits.com.