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Engineering notes, comparisons, and data on fresh air systems and indoor air quality — written for Indian homes, institutions, and anyone trying to breathe better in Delhi NCR.
Delhi Pollution and Life Expectancy: How to Read AQLI EstimatesAQLI estimates population-level gains from sustained reductions in outdoor PM2.5. Understand the data year, assumptions and limits before interpreting a headline.
Delhi NCR Air Quality Year-Round: A Seasonal GuideUnderstand Delhi’s winter smog, summer dust and monsoon changes. Use current AQI and indoor measurements without confusing daily readings with annual exposure.
Are Air Purifiers Enough for Delhi? Filtration vs VentilationA room purifier can reduce particles, but ventilation needs a separate assessment. Compare room coverage, noise, maintenance and outdoor-air supply for Delhi homes.
Indoor CO2 at 1,000 ppm: What the Research Means | aqi0Is 1,000 ppm CO2 a safety limit? Understand ventilation indicators, the limits of cognition research and what to measure in an occupied room.
Bedroom CO2 Overnight: How to Keep a Useful Measurement LogInvestigate overnight bedroom ventilation with a consistent CO2 log. Record occupancy, door positions and equipment settings without assuming a medical cause.
Fresh Air System vs Air Purifier: Choosing for Your HomeCompare room filtration and filtered outdoor-air supply by coverage, ventilation, installation and maintenance. See the aqi0 system price and assessment process.
Positive Pressure Ventilation: How It Works at HomeHow filtered supply air creates positive pressure, what affects airflow between rooms, and what to check before installing a standalone home fresh-air system.
Guides from the aqi0 team on choosing, installing and maintaining a whole-home air purifier, alongside explanations of indoor-air measurements and research.
Watch on YouTube
Short narrated walkthroughs on the aqi0 YouTube channel — 7-8 min each, one new video most weeks.
Do Higher Floors Have Cleaner Air? Why the 20th Floor Won't Save You From PM2.5Do higher floors have cleaner air? Barely — fine PM2.5 mixes through a kilometre-deep layer, so even the 20th floor of a Gurugram tower is many times the WHO limit. Why altitude is a false sense of safety.
Won't We Suffocate If We Seal the House? Why Stale Air — Not Oxygen — Is the Real ProblemWon't you suffocate if you seal the house against the smog? No — oxygen barely moves. The real issue is stale air: bedroom CO2 hits 1,200-2,500 ppm by morning, and a recirculating purifier can't fix it. Filtered fresh air can.
Why an Air Purifier Company Wants to Go Out of BusinessWhy an air purifier company openly wants to put itself out of business — the name as a target, the good days we cheer for, and the day no home needs us
Can One System Clean the Whole Home? Why a Purifier in Every Room Isn't the AnswerOne purifier in the living room isn't enough, and one in every room is expensive and leaves corridors and kitchens uncovered. A single-room purifier is sized for one room — why one whole-home positive-pressure system covers the entire 2-4 BHK at once.
Does Your AC Clean the Air? Why Cooling Isn't CleaningRunning the AC with the windows shut feels clean and fresh — but a split AC just recirculates the same indoor air over a cold coil. Its filter is too coarse for PM2.5, and it adds no fresh air, so CO2 still climbs to 1,200-2,500 ppm overnight. Cold air isn't clean air.
Do Salt Lamps, Ionizers & Diffusers Clean Your Air? (Two of Them Make It Worse)A salt lamp, an ionizer, an oil diffuser — they feel like they clean your air. They don't. The salt lamp does nothing measurable; the ionizer can add ozone and ultrafine particles; the diffuser adds VOCs. None capture PM2.5. Real cleaning means trapping particles and flushing gases — honest mechanical filtration.
How a Whole-Home Air Purifier Actually Works — Every Component, Honestly ExplainedA five-part walkthrough of the aqi0 unit — outdoor intake louver, washable pre-filter, H13 HEPA, EC fan, indoor outlet — following the air outside-to-inside. Plus the one honest decision most brands hide: a standard, off-the-shelf-compatible filter size (no lock-in). Unlike a recirculating purifier it brings in fresh air, so it removes CO2 too — whole-home, one unit, ~30W.
Fundamentals
Sealed Homes and Indoor Air: Plan Ventilation Alongside InsulationAirtight windows can improve comfort, but ventilation still needs planning.
How the aqi0 Whole-Home Air Purifier WorksExplore aqi0’s outdoor unit, H13 filters, airflow, installation requirements and annual care plan. Understand coverage and the conditions behind its performance.
Positive Pressure Ventilation: How It Works at HomeHow filtered supply air creates positive pressure, what affects airflow between rooms…
What Is a Fresh Air System? Installation, Filtration and CareA fresh air system supplies outdoor air. Learn how aqi0 filters that supply, how its standalone installation is assessed…
Reference
The data, standards, and definitive guides.
Stubble Burning and Delhi Pollution: What the Evidence MeansWhy crop residue is burnt, how smoke can reach Delhi, and why fire counts are not a fixed PM2.5 share.
Air Pollution and Dementia: What Research Can and Cannot ShowUnderstand the association between long-term particle pollution and dementia, and why it does not establish prevention benefits from a particular home device.
Does Rain Reduce PM2.5? Delhi’s Monsoon Air ExplainedRain can remove both fine and coarse particles. Understand why monsoon relief varies and how to check indoor particles…
Lung Transplant Questions: Use Specialist Advice and Current InformationLung transplantation is a specialist medical decision. Find authoritative guidance and questions to ask about eligibility, costs, waiting and follow-up in India.
Lung Function in India: Why Reference Values Need Careful InterpretationSpirometry results need clinical interpretation. Population comparisons do not prove an individual’s lung size, genetic limitation or pollution-related damage.
How Much Air Do You Breathe per Day? Understanding the EstimateDaily breathing volume varies with activity and age. Learn the arithmetic behind an air-intake estimate and why inhaled particles are not the…
Gurugram Pollution by Sector: How to Assess a LocationCompare Gurugram homes using station coverage, road exposure, construction and indoor measurements. Avoid unsupported sector rankings and fixed distance claims.
Green Firecrackers: Lower Emissions, Still Air PollutionUnderstand what reduced-emission firecrackers mean, why laboratory reductions cannot predict Delhi’s AQI, and how to plan indoor air care during smoke episodes.
Delhi Truck Traffic and Air Pollution Near Your HomeUnderstand traffic-related particles and gases, why Delhi has no fixed nightly pollution peak…
Delhi Temperature Inversion: Why Winter Pollution Builds UpLearn how temperature inversions and weak mixing affect Delhi’s winter pollution, why no hour is always clean…
Delhi PM2.5 Sources: How to Read the EvidenceUnderstand Delhi’s transport, dust, industry and burning contributions.
Long-Term Air Pollution Exposure: What the Numbers Can Tell YouUnderstand the limits of lifetime exposure estimates, personal health predictions and before-and-after readings when planning indoor-air improvements.
Construction Dust in Delhi NCR: What Residents Can DoIdentify local construction dust, document recurring problems and reduce indoor entry.
Indoor CO2 at 1,000 ppm: What the Research Means | aqi0Is 1,000 ppm CO2 a safety limit? Understand ventilation indicators…
Brick Kiln Pollution in Delhi NCR: Sources and ControlsHow brick kilns contribute to regional pollution, what kiln design and fuel changes can address…
Cleanest Cities: What the 2025 Air Quality Report ShowsSee the cleanest city reported in IQAir’s 2025 dataset, published in 2026…
Bedroom CO2 Overnight: How to Keep a Useful Measurement LogInvestigate overnight bedroom ventilation with a consistent CO2 log. Record occupancy, door positions and equipment settings without assuming a medical cause.
Why AQI Apps Show Different Numbers in IndiaCompare AQI scales, stations, timestamps and pollutants before choosing a reading.
Air Pollution and Sport: Planning Training Around Air QualityUse current local air-quality guidance to plan exercise. Avoid claims that nationality, city averages or a home purifier determine athletic potential.
Air Pollution and Diabetes: Understanding the EvidenceResearch is investigating air pollution and diabetes. Learn why population associations do not establish a personal diagnosis or prove benefits from an…
Air Pollution and Fertility: Interpreting Research Without Product PromisesUnderstand the difference between environmental research and evidence for a fertility intervention. Keep testing, supplements and treatment timing with your clinician.
Delhi Air Pollution at Home: A Practical Action PlanStart with indoor sources, a useful PM2.5 baseline and room-by-room checks. Compare filtration and fresh-air options for a Delhi NCR home.
CO2 Levels in the Bedroom: Measuring and Improving VentilationLearn why bedroom CO2 rises overnight, what 1,000 ppm does and does not mean, how to measure it…
When Will India’s Air Be Clean? Targets and ProgressWhat India’s clean-air programme measures, what the latest PM10 progress shows…
PM2.5 Safe Levels in India: WHO Guidelines vs CPCB StandardsCompare WHO PM2.5 guidelines with India's CPCB standards. Understand daily averages, AQI and home-monitor readings before choosing filtration.
Indoor Air Quality in India: What to Measure and ImproveUnderstand particles, ventilation, gases and moisture in Indian homes. Build a useful measurement record and choose improvements around the actual problem.
India’s PM2.5 and WHO Guidelines: Compare the Right NumbersUnderstand annual versus daily PM2.5, WHO guidelines and Indian standards. Read pollution trends without treating a city average as your personal exposure.
Delhi NCR Air Quality Year-Round: A Seasonal GuideUnderstand Delhi’s winter smog, summer dust and monsoon changes. Use current AQI and indoor measurements without confusing daily readings with annual exposure.
Air Pollution and Children: A Practical Guide for ParentsUnderstand children’s vulnerability to air pollution, plan practical indoor-air checks, and separate equipment claims from medical advice.
Practical guides
VOCs in Indian Homes: Sources, Measurement and ControlUnderstand VOCs from materials and household products, the limits of TVOC sensors, and how source control, ventilation and gas filtration differ.
Room Fresheners and VOCs: Find the Source of the SmellSprays, plug-ins and diffusers add fragrance rather than proving clean air.
Pregnancy and Air Pollution: Questions for Your Care TeamDiscuss air-pollution exposure during pregnancy without relying on personal risk estimates, trimester guarantees or unsupported equipment claims.
Indoor Air for a Newborn: Practical Planning for Delhi NCRPrepare the rooms your baby uses, plan safe equipment placement and maintenance, and discuss pollution concerns with your paediatrician.
New Car Smell and Cabin Air: Practical Questions for OwnersNew-car odour is not an air-quality test. Check the vehicle’s ventilation instructions, cabin-filter compatibility and material information without universal risk claims.
Mosquito Coils and Repellents: Protect Against Bites and SmokeCompare mosquito barriers and labelled repellents without cigarette-equivalent health claims. Keep bite prevention effective while avoiding unnecessary indoor smoke.
New Mattress Smell: Emissions, Certification and SetupLearn what foam certification covers, what to ask about the complete mattress and why there is no universal off-gassing deadline for every…
Low-VOC Paint in India: How to Compare Product EvidenceCompare paint VOC content, emissions tests, tinting, primer and application instructions. Use current product documents rather than generic brand rankings.
Should You Close the Kitchen Door While Cooking?A kitchen door can limit smoke spread only with effective extraction and replacement air.
Kitchen Chimney vs Exhaust Fan: Capture, Ducting and AirflowCompare ducted hoods, recirculating chimneys and wall exhaust fans. Check capture at the cooktop, the outdoor outlet and replacement air before upgrading.
Do Indoor Plants Clean the Air? What the Evidence MeansHouseplant chamber studies do not establish useful home air-cleaning performance. Understand the limits of VOC results, leaf dust and bedroom CO₂ claims.
Indoor Combustion: Cooking, Smoke and Carbon MonoxideUnderstand the different risks from cooking and indoor burning.
Formaldehyde in Furniture: What to Ask Before BuyingCheck composite-wood emissions reports, finished-product details and ventilation. Avoid assuming that a brand, material name or E0 label guarantees room air quality.
Aerosol Deodorants and Indoor Air: What to CheckUnderstand aerosol use, ventilation and product-specific recall evidence. Avoid treating every spray, ingredient or Indian product batch as equivalent.
CO2 in Study Rooms: What Parents and Schools Can MeasureA practical guide to investigating study-room ventilation. Measure conditions…
Carpets and Indoor Air Quality: Buying and Care ChecksCheck carpet, backing, adhesive, cleaning and moisture before installation. Emissions evidence and a realistic care plan matter more than fibre-name claims.
Candles, Incense and Agarbatti: Managing Indoor SmokeBurning candles or incense adds indoor particles. Learn how to reduce smoke sources…
Bathroom Exhaust Fan Test: What a Tissue Can Tell YouCheck whether your bathroom exhaust is drawing air, understand the limits of a tissue test…
Alum (Fitkari) Deodorant: Ingredients and Air-Quality ClaimsConsidering fitkari instead of an aerosol deodorant? Check ingredients, skin suitability and the limits of “natural”, “aluminium-free” and zero-emission claims.
Air Pollution and Older Adults: Home Planning and CarePlan indoor-air improvements for older adults while keeping medical care separate. Check room use, equipment access, measurements and maintenance.
Yoga at Home: Plan Air Quality, Ventilation and ComfortPrepare a home yoga space with useful particle and ventilation checks.
How to Reduce PM2.5 at Home: 10 Practical StepsTen practical steps for reducing indoor PM2.5: control sources, use effective exhaust and filtration, check ventilation and measure results in occupied rooms.
Comparisons & decision guides
H11, H13 and H14 Filters: Grades, Airflow and Buying ChecksUnderstand E11, H13 and H14 classifications, MPPS efficiency and the importance of airflow, filter fit and test reports when choosing home filtration.
Fresh Air System Filter Changes: Schedule, Care and CostThe aqi0 filter schedule: clean the pre-filter every 7–10 days…
ERV vs HRV vs Positive Pressure: What to Compare in IndiaCompare airflow, heat recovery, moisture, filtration and installation. Choose ventilation around the home and climate rather than a one-size-fits-all claim.
EC vs AC Fans: How to Compare Airflow, Power and NoiseCompare EC and AC fans at the same airflow and pressure. Learn what controls running cost…
Activated Carbon Filters: What You Can and Cannot Check at HomeA daylight check cannot establish gas-removal performance. Learn what to ask about carbon media, test conditions…
CADR Explained: How to Compare Air Purifiers for Your RoomUnderstand clean air delivery rate, compare units consistently, and check room volume, fan speed and noise.
Fresh Air System vs Air Purifier: Choosing for Your HomeCompare room filtration and filtered outdoor-air supply by coverage, ventilation, installation and maintenance. See the aqi0 system price and assessment process.
Air Purifier Not Working in Delhi Winter? What to CheckCheck room size, fan speed, filters, indoor sources and outdoor conditions before replacing an air purifier. A practical Delhi winter troubleshooting guide.
Are Air Purifiers Enough for Delhi? Filtration vs VentilationA room purifier can reduce particles, but ventilation needs a separate assessment.
Recently published
Newer deep-dives — automatically listed as each post goes live.
Can Your Body Adapt to Air Pollution? Common QuestionsFeeling accustomed to polluted air is not proof of protection.
Air Pollution and Exposure Reduction: A Guide to the EvidenceRead air-quality guidelines, a children’s cohort study and a filtration trial with their limitations. Separate research findings from home-product health promises.
Most Polluted Cities in India: 2025 Data, 2026 UpdateCompare India’s five highest annual PM2.5 readings in IQAir’s 2025 city dataset.
PM2.5 and the Body: Understanding Particle-Pollution Health EffectsFine particles can affect the lungs and heart. Learn why exposure measurements do not establish a fixed particle journey…
Live AQI for your city
Updated continuously — what’s in the air right now, what the number means, and what to do about it.
What’s coming next
One new deep-dive most weeks. Follow on YouTube, Instagram, or X to see new posts as they go live, or WhatsApp +91 9667672740 to subscribe directly.
Core references
- How positive-pressure ventilation works — the mechanism, explained in three minutes
- Product specifications — full specs, airflow, filtration, warranty
- FAQ — 30+ answered questions on installation, filters, the care plan, and pricing
- Pricing — system ₹82,600 fully installed, annual care plan ₹14,750 a year, aqi0 air-quality monitor ₹4,000 available separately. —
Something you want us to cover?
If there’s an aspect of indoor air quality, HEPA, ventilation, or aqi0’s product that you’d like us to write up — reply on WhatsApp or email [email protected]. We add reader-requested questions to the calendar every month.