7Semi BME688 Environmental Sensor Breakout with Gas, Temperature, Humidity & Pressure Monitoring The 7Semi BME688 Environmental Sensor Breakout is a next-generation module designed for creators, engineers, and researchers looking to capture highly accurate environmental data in one compact board. Built using Bosch Sensortec’s advanced technology, it measures temperature, humidity, barometric pressure, and a wide range of gases - including VOCs, VSCs, CO, and hydrogen. With AI-enabled gas scanning, this sensor offers unmatched flexibility and precision, making it ideal for air quality monitoring, IoT devices, and smart home automation. This tiny board brings premium reliability, fast response times, and long-term stability to any embedded setup. Thanks to support for both I2C and SPI interfaces, the BME688 integrates easily with platforms like Arduino, ESP32, and Raspberry Pi. Whether you’re building an indoor air quality tracker, creating a wearable environmental sensor, or developing research-grade monitoring equipment, this module delivers the depth of data you need. With intelligent gas detection powered by machine learning and a wide operating range, the BME688 excels in environmental sensing, embedded electronics, and modern IoT applications without adding bulk or complexity. Features: Delivers 4-in-1 sensing capabilities with precise measurement of temperature, humidity, atmospheric pressure, and multiple gases in a single compact module. Features AI-enabled gas scanning that detects VOCs, VSCs, carbon monoxide, hydrogen, and other gases using machine-learning-based profiling. Provides high accuracy, low drift, and rapid response speeds for dependable long-term environmental monitoring. Offers flexible integration with both I2C and SPI interfaces for seamless compatibility across microcontrollers and embedded systems. Compact, lightweight design makes it suitable for portable devices, IoT deployments, smart home systems, and environmental research setups. Allows custom tuning of sampling rates, power consumption, and gas sensitivity for specialised applications. Backed by Bosch Sensortec’s reputation for durability, ensuring stability and reliable performance in continuous operation. BME688 4-in-1 Air Quality Sensor Breakout Dimensions: BME688 4-in-1 Air Quality Sensor Breakout Pinouts:

7Semi BME688 Environmental Sensor Probe with Gas, Pressure, Temperature & Humidity Sensor The 7Semi BME688 Environmental Sensor Probe is a compact, AI-enabled environmental monitoring solution designed for precise measurements of temperature, humidity, barometric pressure, and gas levels. Built using the advanced Bosch BME688 sensor, it provides highly accurate, real-time environmental data that supports air quality monitoring, research applications, industrial automation, and smart home systems. Housed in a durable plastic shell, the probe ensures long-term stability while maintaining excellent breathability necessary for accurate gas sensing. This versatile environmental probe uses an I2C digital interface for easy integration with microcontrollers and embedded systems, making it suitable for both portable and fixed installations. With a wide operating range and low power consumption, it delivers stable performance even in harsh or fluctuating environments. AI-powered gas sensing adds advanced analytical capabilities such as IAQ scoring, VOC detection, CO₂-equivalent estimation, and bVOC outputs, making this probe a powerful tool for environmental diagnostics and air-quality-driven automation. Features: Provides simultaneous measurement of temperature, humidity, pressure, and gas concentration, enabling complete environmental assessment in a single compact device. AI-powered gas sensing detects VOCs, CO₂-equivalents, and various gases at ppb-level sensitivity for accurate indoor air quality monitoring. Durable plastic enclosure offers strong resistance to corrosion, dust, and temperature variations while maintaining high permeability for reliable sensing. Wide operational range ensures dependable performance from -40 to 85°C and 0–100% RH, suitable for both indoor and outdoor monitoring environments. Low power design supports battery-operated systems, making it ideal for portable, energy-efficient projects. Mini Round Shell (MRS) connector with a 1m cable provides secure and professional-grade installation flexibility. I2C digital communication interface simplifies integration with embedded systems and common microcontrollers. NIST-traceable factory calibration guarantees accuracy for industrial, regulatory, and research applications. Delivers advanced analytical outputs including IAQ, bVOC, CO₂-equivalent, gas intensity, gas scan, and air quality indexes. Humidity Sensors Pins: Digital Humidity and Temperature Sensor Probe I2C Interfacing with MCU:

Black Oil-resistant Rubber O Shaped Seal Washer (63x3 mm) Black rubber oil sealing O rings, high quality material, oil resistance, abrasion resistance and water proof. O-rings are donut-shaped rings used in industry to seal off or prevent leakage of fluid or gas in an application. It has good resistance to oil, water, high temperature and high pressure resistance. Suitable for both static and dynamic sealing. Use for quick-disconnect fittings, valves, pumps, and other fluid handling products. This nitrile rubber metric O rings works great on electronic equipment, pipes, carburetor repair, tap faucets, pumps, DIY home repair, sensors, trucks, cars, boat, engines, spray guns, pressure washers, pneumatic connection, etc. Provide secure seals for any oil, gas, air, and water seal application. Applications: Can be used in 3D Printers Automotive components Machinery components Bathroom facilities Household electrical appliances Electronic instruments

BME680 Humidity, Pressure, Temperature and Gas Sensor Probe MRS Type -7Semi The BME680 Humidity, Pressure, Temperature and Gas Sensor Probe MRS Type - 7Semi is a robust, high-performance environmental monitoring solution built for demanding applications. Encased in a corrosion-resistant metal housing with a breathable membrane, it incorporates Bosch Sensortec’s BME680 digital 4-in-1 sensor to deliver highly accurate measurements of temperature, humidity, atmospheric pressure, and volatile organic compounds (VOCs). Designed for durability, the sensor excels in challenging environments with high dust, chemical exposure, or extreme temperatures. Its 1-meter cable and I2C interface ensure seamless integration with a wide range of systems operating on 1.7V to 3.6V. Whether deployed in HVAC systems, smart agriculture, industrial automation, or medical setups, the 7Semi BME680 provides stable, long-term data with minimal maintenance, making it a reliable choice for precision environmental sensing. Features: All-In-One Environmental Sensor: Temperature, humidity, barometric pressure, and gas levels (VOCs) are all accurately measured in one small instrument. Durable stainless steel metal casing: The breathable and corrosion-resistant metal shell provides long-lasting protection against harsh circumstances such as dust, humidity, high pressure, and explosive settings. Advanced Gas Detection: Detects a wide spectrum of volatile organic chemicals, which is useful for monitoring indoor air quality and assessing human health. Wide Operating Range: Pressure: 300-1100 hPa, Humidity: 0-100%, Temperature: -40°C to +85°C, making it appropriate for both indoor and outdoor use. I2C Digital Interface: Fully calibrated digital output enables simple integration with microcontrollers and embedded systems. Robust construction for harsh environments: Ideal for usage in vacuum chambers, pipelines, weather stations, soil monitoring systems, humidifiers, and explosive zones. The Mini Round Shell Connector with One-Meter Cable: Features a plug-and-play design and a 4-wire connection, making it ideal for deployment in tight spaces. High filtration efficiency: The stainless steel porous housing with specific pore diameters (5 to 120 microns) provides excellent dust interception and gas permeability. Low power consumption: Suitable for battery-powered and portable applications that demand energy efficiency. Exceptional stability and longevity: Long-term operational stability is supported by Bosch's established sensor technology.

MQ-136 Hydrogen Gas Sensor For Hydrogen Sulfide Detector Module MQ136 Gas Sensor can be used to monitor the concentration of Hydrogen Sulfide gas. This Module simplifies using the MQ-136 gas sensor by providing digital as well as analog output which can be interfaced with Microcontrollers, Arduino, and Raspberry pi. The sensitive material of the MQ136 gas sensor is SnO2, which with lower conductivity in clean air. When the target Hydrogen sulfide gas exists, the sensor’s conductivity is higher along with the Hydrogen sulfide concentration rising. Please use a simple electric circuit, Convert the change of conductivity to the corresponding output signal of gas concentration. MQ136 gas sensor has a high sensitivity to Hydrogen sulfide, Low sensitivity to other combustible gas. It is at a low cost and suitable for different applications. Applications: Domestic Hydrogen sulfide detector Industrial Hydrogen sulfide detector Portable Hydrogen sulfide detector Gas leak monitoring device suitable for home or factory, suitable for liquefied gas, butane, propane, methane, alcohol, hydrogen, smoke, and other monitoring devices.

MQ-5 Gas Sensor The MQ-5 gas sensor is a device that is used to detect the presence of various gases, including methane, propane, and natural gas. It operates by measuring the resistance of a metal oxide semiconductor (MOS) material to changes in the concentration of the target gas in the air. The MQ-5 sensor is sensitive to a wide range of gases, making it suitable for use in a variety of applications, such as detecting gas leaks in homes and buildings, monitoring indoor air quality, and detecting the presence of harmful gases in industrial settings. The sensor has a fast response time and high sensitivity, making it capable of detecting small concentrations of gases. The MQ-5 gas sensor consists of a sensing element, and a heating element. The sensing element is made of a metal oxide material that is sensitive to the target gas. The heating element is used to maintain the temperature of the sensing element at a constant level, which is necessary for accurate gas detection. If you want to use this MQ-5 Gas Sensor Module with Arduino, for that you will need Arduino jumper wires buzzer or siren Applications: Detecting LPG Detecting natural gas Detecting coal gas Detecting alcohol Detecting cooking fumes Detecting cigarette smoke read our blog explaining all about mq gas sensor , provides comprehensive information about MQ gas sensors, specifically the MQ series of gas sensors

MQ131 Ozone Gas Detection Module The MQ131 gas sensor module is a device that can detect the presence of ozone gas (O3) in the air. It is commonly used in applications such as air quality monitors and industrial control systems. The MQ131 sensor operates by using a chemical reaction between the ozone gas and a conductive metal oxide to produce a current. The magnitude of the current is proportional to the concentration of ozone gas in the air. The sensor can be used to detect ozone gas concentrations in the range of 0.05-10 ppm. Ozone is a toxic gas that can be harmful to humans at high concentrations. It is recommended to use the MQ131 sensor with caution and to take appropriate safety measures when working with it. The sensitive material of the MQ131 gas sensor is O3 SnO2, which with lower conductivity in clean air. When Ozone gas exists. The sensor’s conductivity is higher along with the gas concentration rising. Please use a simple electro circuit, Convert the change of conductivity to corresponding output signal of gas concentration. MQ131 gas sensor has a high sensitivity to Ozone, also sensitive to O3 CL2, NO2, etc. Features: Detection Gas: Ozone (O3). Detection Range: 10 to 1000 ppb (parts per billion). Sensor Type: Semiconductor. Operating Voltage: Typically 5V DC. Output: Analog signal output, with a voltage range of 0-5V. Sensitivity: High sensitivity to ozone and other strong oxidizing gases like chlorine (Cl2) and nitrogen dioxide (NO2). Response Time: Fast response and recovery. Durability: Long service life and reliable stability. Interface: Easy to interface with microcontrollers like Arduino and Raspberry Pi. Power Consumption: Low power consumption, suitable for continuous monitoring APPLICATIONS: Domestic ozone concentration alarm Industrial ozone concentration alarm Portable ozone concentration detector

DFRobot Fermion MEMS Methane CH4 Gas Sensor (Breakout, 1-10000ppm) The DFRobot Fermion MEMS Methane CH4 Gas Sensor is a compact and energy-efficient breakout board designed to detect methane concentrations from 1 to 10,000ppm. Powered by advanced MEMS technology, it features ultra-low power consumption (<20mA), minimal heat generation, and a fast response time. Its small size (13x13x2.5mm) makes it perfect for integration into gas leak detectors, safety systems, and environmental monitoring devices. Ideal for fire prevention and combustible gas detection, this sensor is part of a versatile MEMS series supporting multiple gas types for customizable sensing solutions. DFRobot Methane CH4 Gas Sensor Interfacing with Arduino Circuit Diagram Precautions for Use Remove the protective film before using the sensor. Avoid exposure to volatile silicon compounds (e.g., silicone adhesives, hair gels, silicone rubber). Do not expose the sensor to high concentrations of corrosive gases (e.g., H?S, SO?, Cl?, HCl). Prevent contamination from alkalis, alkali metal salts, and halogens. Avoid prolonged exposure to extreme environments (high temperature, humidity, or pollution). Keep the sensor away from water, condensation, and freezing conditions. Minimize mechanical stress—avoid strong vibration, impact, or dropping. Do not use this sensor in systems where failure could affect personal safety. If unused for a long time, preheat the sensor for at least 24 hours before reuse. Features Compact size: only 13 × 13 × 2.5mm, ideal for space-constrained applications Low power consumption: operating current less than 20mA High sensitivity with fast response and quick recovery time Built using advanced MEMS (Micro-Electromechanical Systems) technology Applications Health applications Fire detection Industrial safety Environmental monitoring Indoor air quality

DFRobot Gravity PH3 Gas Sensor (Calibrated)  I2C, UART and Analog This Gravity PH3 Sensor is a very useful device to find out the amount of phosphine gas around you. It's perfect if you're working on projects for factories, checking safety in mines, or just want to know the air quality in places like godowns or closed rooms. The sensor has a special part (electrochemical probe) that is already fine-tuned at the factory. This means you can quickly and accurately measure Phosphine Gas Sensor levels right out of the box, without needing to do any complex setup. It’s also made to be tough and reliable. You can easily connect this PH3 Sensor to popular electronics boards like Arduino, ESP32, or Raspberry Pi using the simple Gravity connector. It's flexible because it can send data through I2C, UART, or even as an analog voltage signal, whichever suits your project. The sensor also has smart features like automatically adjusting for temperature changes to keep the readings correct, and it can even set off an alarm if the gas level gets too high. It's built to last for over two years, making it a good choice for your gas sensing needs. Features Gas Detected: Phosphine (PH3) Measures Up To: 0 to 1000 ppm (parts per million) Output Types: Analog, I2C, and UART Ready to Use: Factory calibrated (already set up) Connects To: Arduino, ESP32, Raspberry Pi, etc. Good Quality: Very sensitive and doesn't get easily disturbed Long Life: Can work for more than 2 years (in air) Power Needed: 3.3 Volts to 5.5 Volts DC I2C Setup: Has 32 I2C addresses you can choose from

Fermion MEMS Gas Detection Sensor Carbon Monoxide (CO) (Breakout, 5-5000ppm) Let me present you the Fermion MEMS Gas Detection Sensor for Carbon Monoxide (CO). It's incredibly cool since it's so small—only 13x13x2.5mm in size. Despite its small size, this carbon monoxide detector is extremely efficient, using less than 20 mA of electricity and producing almost little heat. This carbon monoxide gas detector sensor also operates quite rapidly. It boots up quickly and provides readings immediately. It is capable of detecting airborne carbon monoxide at concentrations as low as 5 parts per million and as high as 5000 parts per million. That makes it perfect for setting up alarms in homes or making portable detectors. And here’s the best part—it’s part of a whole series of sensors. There are 11 different kinds, for things like formaldehyde, methane, and more. You can mix and match them to create a system that’s exactly right for what you need. Whether you want to make homes safer, monitor air quality in schools, or keep an eye on conditions in a factory, this sensor is ideal. It’s simple to use and does a great job of keeping you safe from carbon monoxide. Kindly Note: This CO  gas detector sensor can only perform qualitative measurements. For quantitative measurements, consider purchasing the Gravity: Factory Calibrated Electrochemical CO Sensor (0-1000 ppm, I2C & UART). Features: 13x13x2.5 mm in size, perfect for small spaces. Consumes little energy while operating effectively. Makes use of cutting-edge MEMS technology to detect CO with accuracy. Allows for speedy recovery and detection times. Precautions for Use: Before use, make sure to remove any protective film covering the sensor. Keep the sensor away from areas where volatile silicon compounds are present, such as silicone adhesive or hair gel, to prevent interference. Do not expose the sensor to high concentrations of corrosive gases like H2S, SOX, Cl2, HCl, as they can damage it. Ensure the sensor is not contaminated by alkalis, alkali metal salts, or halogens. Avoid exposing the sensor to extreme environments with high temperatures, humidity, or pollution levels for extended periods. Protect the sensor from water, condensation, and freezing temperatures to maintain its functionality. Minimize vibration, impacts, and avoid dropping the sensor to prevent damage. Do not use the sensor in applications where personal safety could be at risk. If the sensor will not be used for a while, it's recommended to preheat it for at least 24 hours before reactivating to ensure proper performance. Wiring Diagram to Connect With Arduino UNO: Applications: Used for carbon monoxide detection to ensure safety and monitor air quality. Essential for detecting carbon monoxide in metallurgical processes to protect workers. Critical for carbon monoxide detection in mines to prevent exposure. Used to detect carbon monoxide emissions and assess air quality in urban and industrial areas.