Clean Air Blog

Whether it's moving into a new home or doing some DIY renovations, many of us will be familiar with that 'new home smell'. Unfortunately, behind that smell are a number of potentially dangerous chemicals or VOCs such as formaldehyde! For some this may cause headaches, dizziness and other health issues. This brings us to the question: How do you keep yourself safe from these VOCs and can an air purifier help? The good news is there are ways to mitigate these VOCs and the right air purifier can definitely help! Understanding VOCs and Their Sources VOCs are emitted as gases from certain solids or liquids. Common sources in new builds and renovations include: Formaldehyde: Found in building materials like plywood, particleboard, and adhesives. Benzene: Emitted from paints, glues, and cleaning products. Toluene: Present in paints, paint thinners, and adhesives. Health Impacts Exposure to VOCs can cause, amongst other things: Headaches Dizziness Respiratory issues Eye, nose, and throat irritation Monitoring VOC levels with an Air Quality Monitor Using an air quality monitor with a TVOC sensor, like the QP Pro 2 or the Temtop M10 can help you gauge VOC levels in your home. While you won't see levels of each specific chemicals, measuring the VOCs will help give a picture of baseline levels of VOCs in the air and can show the effectiveness of different tactics in reducing VOCs. Effective Strategies for Reducing VOCs Ventilation The most effective way to reduce VOCs is through ventilation: Mechanical Ventilation: Use exhaust fans or air exchangers like HRV systems. Natural Ventilation: Open windows and doors to create a strong cross breeze. Formaldehyde Cookouts These are a way to force more formaldehyde from building materials, furniture etc. in a shorter period of time. Note you should avoid being inside when the cookout is run. Smart Air have written a detailed guide here, however the basic process is: 1. Close windows/doors and increase temperature, through heating or naturally with sunlight. Aim for 30+ degrees if possible. 2. Keep the temperature up for a few hours, ideally 6-8 if possible. 3. When you return, open windows and doors to remove the formaldehyde from the air and return the space to a normal temperature. 4. Repeat this several times  Air Purifiers with Activated Carbon Filters An air purifier with a carbon (VOC) filter can provide additional assistance, especially when ventilation isn't possible. Key Factors to Consider: Amount of Carbon: This determines the amount of VOCs which can be filtered before the filter becomes saturated. Some mesh-style "carbon filters" may last only a few minutes in high VOC environments. Separate Carbon Filter: Allows for easy replacement when needed, as in high VOC situations the Carbon Filter will likely need replacing well before the HEPA filter. Our Recommended Purifiers: Sqair: 140g of activated carbon per filter. SA600: 170g per filter (2 per purifier). Blast Mini: 550g of activated carbon per filter (optional extra). Blast: 0.9kg of activated carbon per filter (optional extra). For additional VOC cleaning power, you can remove the HEPA filter and use multiple carbon filters in our purifiers.   Wrapping Up VOCs are an unfortunate reality in newly built or renovated homes. It's essential to tackle these to maintain good indoor air quality and health. Ventilation, both mechanical and natural, is the most effective strategy. Additionally, using air purifiers with plenty of activated carbon can provide assistance, especially when ventilation is not possible. Formaldehyde Cookouts are an additional tool to help lower the levels of formaldehyde being released.

Odours and chemical smells are one of the most common reasons people start looking into air purifiers. Whether it’s cooking smells, pet odours, smoke, or off-gassing from everyday products. Air purifiers can help reduce odours and VOCs, but only when they’re used correctly and paired with the right type of filter. They’re also not a silver bullet, ventilation still plays a critical role. This guide explains: What causes odours and VOCs indoors How air purifiers help (and where they don’t) What actually matters in a carbon filter How to set realistic expectations Quick Summary: Air Purifiers and Odours Odours are caused by gases (VOCs), not particles HEPA filters alone do not remove odours Activated carbon is required for odour and VOC reduction More carbon = better performance (measured by weight) Ventilation is still the most effective way to clear smells Table of contents 1. What causes odours and VOCs indoors? 2. HEPA vs carbon: Why odours are different 3. How carbon filters actually work 4. Why "carbon filter included" often means very little 5. Realistic expectations: what air purifiers can (and can’t) do 6. Odours & VOCs in specific situations 7. How our purifiers handle odours and VOCs 8. Carbon filter lifespan: a common question 1. What causes odours and VOCs indoors? Most odours indoors come from volatile organic compounds (VOCs). These are gases released by everyday activities and materials. Common sources include: Cooking (especially frying, oils, spices) Pet odours and litter trays Smoke (fires, wood burners, tobacco) Cleaning products and sprays Paints, glues, sealants, and new furniture Workshops, 3D printing, resin, and hobby spaces Because VOCs are gases, they behave very differently to dust or pollen. This is why filter choice matters so much. 2. HEPA vs carbon: Why odours are different This is a key point that’s often misunderstood. HEPA filters capture particles like dust, pollen, mould spores, and PM2.5. They are excellent at this, but they do not remove gases or smells. To reduce odours and VOCs, you need activated carbon filtration. If a purifier doesn’t contain meaningful amounts of activated carbon, it won’t do much for odours. Regardless of how good other filter(s) are. 3. How carbon filters actually work Activated carbon works by adsorbing gases onto its surface. The effectiveness depends on three main factors: 1. Carbon Form Carbon pellets or granules are far more effective than thin carbon-coated meshes. 2. Carbon Quantity More carbon means more surface area and longer‑lasting odour reduction. This is why carbon weight (grams or kilograms) matters. 3. Airflow (CADR) A purifier needs sufficient airflow to pull odours and VOCs from around the room and pass them through the carbon filter. If airflow is too weak, much of the polluted air simply never reaches the filter. This is a common issue with small or low‑powered purifiers marketed for odours. Even if they contain carbon, insufficient airflow means odours don’t get a proper chance to be treated. 4. Why "carbon filter included" often means very little Many air purifiers advertise that they include a “carbon filter” or “VOC layer”, but in practice this can be: A very thin carbon sheet Only a small amount of carbon Designed more for marketing than performance These filters may slightly reduce smells at first, but they saturate quickly and provide limited ongoing benefit. 5. Realistic expectations: what air purifiers can (and can’t) do Air purifiers with proper carbon filtration can: Reduce everyday odours over time Lower background VOC levels Improve perceived air freshness They won't: Instantly remove strong smells Eliminate odours embedded in walls, carpets, or furniture Replace ventilation For persistent or strong odours, ventilation is still the most effective solution. That means opening windows and doors, or using mechanical systems like HRV, extraction fans and kitchen rangehoods. 6. Odours & VOCs in specific situations Cooking Smells Carbon filters can help reduce lingering smells, but kitchen extraction and ventilation remain important. Pet Odours Carbon helps with odours; HEPA helps with dander and allergens. To learn more, check out our article on purifiers and pets Smoke Smells Air purifiers can help with airborne smoke particles (HEPA filtration) and some smells. However smoke, especially from cigarettes often permeates furnishings and building materials. This means a purifier won't provide as much help when it comes to removing smells from a long term smoker house. Workshops, resin, and 3D printing Carbon filtration becomes much more important here. Many people underestimate how much carbon is needed for chemical vapours. For ongoing hobby or workshop use, larger carbon amounts and good ventilation are strongly recommended. New home smells and renovations If you’re dealing with new home smells, renovations, paint, or off‑gassing materials, we cover that in more detail in our dedicated article on new home smells and VOCs. VOCs in New Homes & Renovations Guide 7. How our purifiers handle odours and VOCs We focus on real, measurable carbon filtration, paired with enough airflow to actually circulate room air. Smart Air Sqair Carbon filter included as standard 140g of carbon pellets per filter Additional carbon filters can replace the HEPA for heavier VOC use Add up to 5 extra carbon filters in total for increased odour reduction View Smart Air Sqair Smart Air SA600 2x Carbon filters included as standard 170g carbon pellets per filter Can add 2 additional carbon filters for higher VOC loads Quiet enough to run continuously View Smart Air SA600 Smart Air Blast Mini Mk II Optional carbon filter 550g carbon pellets per filter Quiet enough to run continuously View Smart Air Blast Mini Mk II Smart Air Blast Mk II Optional carbon filter 900g carbon pellets per filter Quiet enough to run continuously View Smart Air Blast Mk II 8. Carbon filter lifespan: a common question Carbon filter lifespan is very difficult to estimate, as it can vary massively depending on: Type and concentration of VOCs Room size and airflow How often the purifier is running In light odour environments, carbon filters may last many months. In heavier VOC settings (painting, resin, smoke), they can saturate much faster. Weaker carbon filters may only last a matter of hours in these situations. Many people replace carbon filters when odours stop improving or based on the smell test Final Takeaway: Air purifiers can play a useful role in managing odours and VOCs - but only when they include meaningful amounts of activated carbon and enough airflow to circulate room air effectively. For best results, pair air purification with good ventilation and realistic expectations. Do air purifiers remove smells completely? Air purifiers can reduce odours over time, but they rarely eliminate them completely. Strong or persistent smells often come from surfaces, furnishings, or building materials, which air purifiers can’t clean. Ventilation remains essential. Do HEPA filters help with odours? No. HEPA filters are designed to capture particles like dust, pollen, and smoke particles, but they do not remove gases or smells. Odour and VOC reduction requires activated carbon. How much carbon do I need for odours? There’s no single answer, but more carbon generally performs better. Purifiers with only a thin carbon layer may help briefly, while units with hundreds or thousands of grams of carbon provide longer‑lasting odour reduction. Can air purifiers help with smoke smells? They can help reduce airborne smoke particles and some smell, but smoke, especially from cigarettes often penetrates walls, carpets, and furniture. In those cases, air purifiers have limited impact on lingering odours. Relevant Articles: The Best Air Purifiers in New Zealand: 2025 Comparison Read more New Home Smell Making You Sick? Tackle VOCs with These Tips Read more How to Stay Safe in Smoke | NZ Guide to Clean Indoor Air Read more