{"product_id":"gravity-sfa40-formaldehyde-hcho-sensor-0-2000ppb-20ppb-accuracy","title":"Gravity: SFA40 Formaldehyde (HCHO) Sensor (0-2000ppb, ±20ppb Accuracy)","description":"\u003ch2\u003eIntroduction\u003c\/h2\u003e\n\u003cp\u003eGravity: SFA40 HCHO Sensor is a high‑precision electrochemical module built for accurate formaldehyde monitoring in indoor environments. Powered by the Sensirion SFA40 sensing chip, this Gravity‑series air quality sensor selectively detects HCHO molecules while minimizing interference from common household vapors such as alcohol or perfumes. Integrated SHT4x temperature and humidity sensing enables automatic environmental compensation, delivering stable and reliable readings for air monitoring systems. With a convenient Gravity I2C interface compatible with Arduino platforms and other development boards, this environmental sensing module integrates easily into smart home projects, HVAC monitoring equipment, and experimental air‑quality instrumentation.\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003eZero False Alarms with Selective Electrochemical Detection\u003c\/b\u003e\u003c\/p\u003e\n\u003cp\u003eTraditional gas sensors frequently produce false alerts when exposed to harmless household scents such as citrus oils, cleaning products, or hand sanitizer. This electrochemical formaldehyde detection module addresses that challenge through advanced electrode materials engineered for extremely low cross‑sensitivity to ethanol (below 0.3%). Such selective detection ensures that rising measurements correspond to genuine formaldehyde concentration changes rather than background odors, making this indoor air quality monitoring board suitable for reliable safety alerts and environmental diagnostics.\u003c\/p\u003e\n\u003cp\u003e\u003cimg\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0668\/0641\/5437\/files\/E34024-content1.webp?v=1791324134\" alt=\"\"\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003eLaboratory‑Grade Sensitivity Down to 20 ppb\u003c\/b\u003e\u003c\/p\u003e\n\u003cp\u003eDetecting trace‑level formaldehyde requires extremely high sensing resolution. This precision HCHO monitoring module provides a detection threshold as low as 20 ppb, enabling identification of subtle off‑gassing from building materials, furniture coatings, or interior finishes. Such sensitivity allows environmental researchers, air‑quality developers, and safety monitoring systems to capture concentration changes that many conventional gas sensors overlook. Accurate trace detection makes this air pollution measurement unit suitable for both residential monitoring devices and laboratory‑level experimental setups.\u003c\/p\u003e\n\u003cp\u003e\u003cimg\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0668\/0641\/5437\/files\/E34024-content2.webp?v=1791324150\" alt=\"\"\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cb\u003eIntegrated Temperature and Humidity Compensation\u003c\/b\u003e\u003c\/p\u003e\n\u003cp\u003eEnvironmental conditions such as heat and humidity can introduce measurement drift in gas sensing systems. This formaldehyde sensing board integrates an onboard SHT4x environmental sensor that continuously measures ambient temperature and humidity, enabling automatic real‑time compensation. Such embedded calibration maintains measurement stability across different environments including humid basements, residential living spaces, and office interiors. Simultaneous monitoring of HCHO concentration, temperature, and humidity also provides a richer environmental data set for smart air monitoring platforms.\u003c\/p\u003e\n\u003cp\u003e\u003cimg\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0668\/0641\/5437\/files\/E34024-content3.webp?v=1791324165\" alt=\"\"\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cimg src=\"https:\/\/cdn.shopify.com\/s\/files\/1\/0668\/0641\/5437\/files\/E34024-content4.webp?v=1791324185\" alt=\"\"\u003e\u003c\/p\u003e\n\u003cp\u003eThis electrochemical air quality module enables accurate formaldehyde monitoring for a wide range of environments including homes, laboratories, and smart buildings. Integration into air purifiers, ventilation controllers, and indoor environmental monitoring stations allows automatic response when HCHO concentrations increase. Such capability supports safer living spaces, energy‑efficient ventilation control, and experimental indoor air research projects.\u003c\/p\u003e\n\u003ch2\u003eFeatures\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eSensirion SFA40 electrochemical formaldehyde sensing chip\u003c\/li\u003e\n\u003cli\u003eHigh sensitivity with detection threshold down to 20 ppb\u003c\/li\u003e\n\u003cli\u003eMeasurement range up to 0–2000 ppb\u003c\/li\u003e\n\u003cli\u003eExtremely low cross‑sensitivity to ethanol (\u0026lt;0.3%) to prevent false alarms\u003c\/li\u003e\n\u003cli\u003eIntegrated SHT4x sensor for temperature and humidity compensation\u003c\/li\u003e\n\u003cli\u003eSimultaneous output of HCHO concentration, temperature, and humidity\u003c\/li\u003e\n\u003cli\u003eGravity I2C interface for easy integration with microcontroller platforms\u003c\/li\u003e\n\u003cli\u003eSuitable for smart home, HVAC monitoring, and environmental research\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eApplications\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eSmart Home Air Guardians: Build a monitor that alerts when furniture or interior materials release formaldehyde.\u003c\/li\u003e\n\u003cli\u003eAutomated Ventilation Systems: Trigger fans or window actuators when HCHO concentration exceeds safe limits (\u0026gt;80 ppb).\u003c\/li\u003e\n\u003cli\u003eSmart Air Purifiers: Activate filtration systems only when pollutants are detected, improving energy efficiency.\u003c\/li\u003e\n\u003cli\u003ePortable Air Quality Inspectors: Develop handheld monitors for checking indoor environments such as homes, offices, or vehicle cabins.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eSpecification\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eTypical accuracy: ±20ppb or ±20% m.v (@0~200ppb measurement range)\u003c\/li\u003e\n\u003cli\u003eFormaldehyde measurement range: 0~2000ppb\u003c\/li\u003e\n\u003cli\u003eCross-sensitivity to ethanol: 0.3%(15ppb output in 5ppm ethanol)\u003c\/li\u003e\n\u003cli\u003eStartup time after power on: 10min\u003c\/li\u003e\n\u003cli\u003eResponse time: ＜2min\u003c\/li\u003e\n\u003cli\u003eLifttime: ＞ 6years\u003c\/li\u003e\n\u003cli\u003eLong-term drift: ＜5ppb or ＜5% of the measured value, whichever is larger per year\u003c\/li\u003e\n\u003cli\u003eSupply Voltage: 3.3–5V\u003c\/li\u003e\n\u003cli\u003eOperating Temperature: 0~50℃\u003c\/li\u003e\n\u003cli\u003eOperating Humidity：10~90%R.H\u003c\/li\u003e\n\u003cli\u003eOperating Current: 80μA(Average@2Hz), 2mA(peak)\u003c\/li\u003e\n\u003cli\u003eSize: 32 * 22mm\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eShipping List\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003eGravity: SFA40 HCHO Sensor x1\u003c\/li\u003e\n\u003cli\u003eGravity 4pin sensor cable x1\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eDocuments\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003ca href=\"https:\/\/wiki.dfrobot.com\/sen0661\/\" target=\"_blank\"\u003eProduct Wiki\u003c\/a\u003e\u003cbr\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"DFRobot","offers":[{"title":"Default Title","offer_id":67580641181773,"sku":"E34024-001","price":84.6,"currency_code":"AUD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0668\/0641\/5437\/files\/E34024-win1.jpg?v=1791324215","url":"https:\/\/www.mlab.com.au\/products\/gravity-sfa40-formaldehyde-hcho-sensor-0-2000ppb-20ppb-accuracy","provider":"MLAB","version":"1.0","type":"link"}