# Gas and Air Quality Sensors

> Sensors and modules for gas, CO2, VOC, dust and air quality: MQ-2/3/4/5/6/7/8/9, MICS, SGP41, SCD41, BME680

- Shop: [Sigmanortec.ro](https://sigmanortec.ro/en/llms.txt)
- Category page: https://sigmanortec.ro/en/gas-and-air-quality-sensors
- Category: Mechatronics and IoT > Sensors and Modules > Gas and Air Quality Sensors
- Prices: RON, VAT included; prices and stock as of 2026-10-22 01:32 (Europe/Bucharest)

## Products (19)

### Air quality sensor module, VOC, MICS-4514, 5V
- Page: https://sigmanortec.ro/en/air-quality-sensor-module-voc-mics-4514-5v
- Details: https://sigmanortec.ro/en/llms/p/2342.md
- Price: 199.17 RON
- Availability: Out of stock
- Reference: 88153 · EAN: 5945255201725
- Specifications: Input Voltage: 5 V; Input Voltage Type: “DC” in Romanian can mean **“de ce”**, which translates to **“why”** in English.; Measured quantity: VOC; Sensor used: MICS-4514

Air quality sensor module with MICS-4514 sensor, 5 V DC supply, Arduino compatible. Detects reducing gases (CO, NH3, ethanol, H2, methane/propane/isobutane) on the RO output and oxidizing gases (NO2) on the OX output, providing two separate analog outputs. Includes an En pin for heater activation. Current draw ~25-35mA, operating temperature -20~50°C, dimensions 17x14 mm.

### CO2 sensor module, temperature and humidity, SCD41, I2C, 2.4-5V
- Page: https://sigmanortec.ro/en/co2-sensor-module-temperature-and-humidity-scd41-i2c-24-5v
- Details: https://sigmanortec.ro/en/llms/p/2324.md
- Price: 201.13 RON
- Availability: Out of stock
- Reference: 88154 · EAN: 5946366996227
- Specifications: Supply Voltage: 2.4; Maximum Input Voltage: 5; Interface / Control: I2C

Compact air quality monitoring module, measures CO2, temperature and humidity, ideal for IoT, HVAC and automation. Communicates quickly via I2C at address 0x62, operates at 2.4-5.5 V for compatibility with 3.3V and 5V, offers CO2 measurement up to 40000 ppm and low consumption for continuous or low-power use.
This module integrates the Sensirion SCD41 sensor, with true carbon dioxide measurement using the photoacoustic NDIR principle, along with ambient temperature and humidity. It is intended for air quality monitoring applications, automation, HVAC systems, weather stations, and IoT projects.

### Air quality sensor module, VOC, MICS-5524, 5V
- Page: https://sigmanortec.ro/en/air-quality-sensor-module-voc-mics-5524-5v
- Details: https://sigmanortec.ro/en/llms/p/2297.md
- Price: 55.60 RON
- Availability: In stock; 1-2 zile
- Reference: 88120 · EAN: 5944228247814
- Specifications: Input Voltage: 5 V; Input Voltage Type: “DC” in Romanian can mean **“de ce”**, which translates to **“why”** in English.

Air quality sensor module with MICS-5524, 5V DC power supply, compatible with Arduino and other development boards. Detects CO, NO2, H2, NH3, CH4, C3H8, C4H10, with analog output on a single pin. Features an Enable pin (iEn) for heater control and low power consumption. Operating temperature: -20°C to +50°C. Dimensions: 19.2 x 13mm. Current consumption: ~25-35mA.

### Environmental sensor module, ENS160+AHT21, temperature, humidity, VOC, 5V
- Page: https://sigmanortec.ro/en/environmental-sensor-module-ens160aht21-temperature-humidity-voc-5v
- Details: https://sigmanortec.ro/en/llms/p/2290.md
- Price: 53.51 RON
- Availability: In stock; 1-2 zile
- Reference: 88121 · EAN: 5948292393538
- Specifications: Input Voltage: 5 V; Input Voltage Type: “DC” in Romanian can mean **“de ce”**, which translates to **“why”** in English.

Compact solution for monitoring indoor air quality, measuring temperature and humidity and detecting VOC for smart home and HVAC automation. It connects quickly to Arduino and other platforms via I2C or SPI, operates at 5V with low consumption of approximately 10mA, offers a wide measurement range and is easy to mount due to its small size.
The ENS160 + AHT21 module is a compact solution for complete indoor air monitoring, combining temperature and humidity measurement with gas and volatile organic compound detection.

### NH3 and CO Gas Sensor, MQ-137, Ammonia, Analog and Digital, 5V
- Page: https://sigmanortec.ro/en/nh3-and-co-gas-sensor-mq-137-ammonia-analog-and-digital-5v
- Details: https://sigmanortec.ro/en/llms/p/2232.md
- Price: 174.88 RON
- Availability: In stock; 1-2 zile
- Reference: 88165 · EAN: 5944832002267
- Specifications: Supply Voltage: 5; Input Voltage Type: “DC” in Romanian can mean **“de ce”**, which translates to **“why”** in English.

MQ-137 gas sensor module for detecting ammonia (NH3) and carbon monoxide (CO), with analog output 0-5V and digital TTL output via LM393 comparator. Adjustable sensitivity threshold via potentiometer, response time under 1s, measurement range 10-300ppm. Power supply 5V DC, dimensions 28 x 20mm, compatible with Arduino, ESP32 and Raspberry Pi. LED indicator for power and signal.

### CO2 sensor MH-Z19C, UART and PWM output, NDIR, 400-5000ppm
- Page: https://sigmanortec.ro/en/co2-sensor-mh-z19c-uart-and-pwm-output-ndir-400-5000ppm
- Details: https://sigmanortec.ro/en/llms/p/2212.md
- Price: 288.17 RON
- Availability: In stock; 1-2 zile
- Reference: 88051 · EAN: 5943607239709

CO2 sensor MH-Z19C using NDIR principle with temperature compensation, measurement range 400-5000ppm. UART TTL 3.3 V and PWM outputs, 5.0 V DC supply, average current under 40 mA, peak current up to 125 mA. Warm-up time ~1 minute, response time T90 under 120 s. Operating temperature -10 to +50 C, humidity 0-95% RH non-condensing. Dimensions 33 x 20mm. Works with Arduino, ESP, STM32.

### SGP41 air quality sensor module, VOC and NOx, I2C, 3.3V
- Page: https://sigmanortec.ro/en/sgp41-air-quality-sensor-module-voc-and-nox-i2c-16v
- Details: https://sigmanortec.ro/en/llms/p/2213.md
- Price: 67.11 RON
- Availability: In stock; 1-2 zile
- Reference: 88052 · EAN: 5940328302897
- Specifications: Input Voltage: 1.6 V; Input Voltage Type: “DC” in Romanian can mean **“de ce”**, which translates to **“why”** in English.

Compact module for real-time air quality monitoring, detects VOC and NOx with Sensirion MOX technology, I2C communication for quick integration with Arduino, ESP32, Raspberry Pi or STM32, operates at low 3.3V voltage ideal for battery-powered devices, suitable for smart home, HVAC, purifiers and portable weather stations.
Module based on the SGP41 sensor, designed for measuring air quality, compatible with Arduino and other development boards, used in smart home applications, HVAC, air purifiers or portable weather stations.

### CO, VOC, NO2, NH3 sensor module, MICS-6814, 5V
- Page: https://sigmanortec.ro/en/co-voc-no2-nh3-sensor-module-mics-6814-5v
- Details: https://sigmanortec.ro/en/llms/p/1785.md
- Price: 205.17 RON
- Availability: In stock; 1-2 zile
- Reference: 9674 · EAN: 5947140560108
- Specifications: Input Voltage: 5 V; Input Voltage Type: “DC” in Romanian can mean **“de ce”**, which translates to **“why”** in English.

Air quality monitoring module, detects CO, VOC, NO2 and NH3 with the MICS-6814 sensor, ideal for Arduino projects, smart home automation and industrial applications. It operates at 5V, offers separate analog outputs for each gas, has low consumption of approximately 30mA and compact dimensions of 17 x 14 mm.
Air quality sensor, compatible with Arduino and other development boards, is an advanced device designed to detect and measure the concentrations of carbon monoxide (CO), volatile organic compounds (VOC), nitrogen dioxide (NO2) and ammonia (NH3) in diverse environments.

### Dust particle sensor, GP2Y1014AU0F, 5V
- Page: https://sigmanortec.ro/en/dust-particle-sensor-gp2y1014au0f-5v
- Details: https://sigmanortec.ro/en/llms/p/660.md
- Price: 45.44 RON
- Availability: In stock; 1-2 zile
- Reference: 33129 · EAN: 5945827313832
- Specifications: Input Voltage: 5 V

Sensor for monitoring fine dust, pollen or smoke particles in Arduino projects and other development boards, operates at 5V and has analog output for fast integration, good sensitivity for air quality measurements and stable response, low current with peaks up to 20mA. Comes with cable with connector, 220uF capacitor and 150 ohm resistor for easy connection.
Particle and dust sensor, compatible with Arduino and other development boards, which can be used to detect fine particles of dust, pollen, smoke particles, and so on. It uses a SAHRP sensor and comes with a cable with a connector, a 16V 220uF capacitor and a 150 ohm resistor.
Specifications:
Supply voltage: 5VDC …

### MQ-2 gas sensor
- Page: https://sigmanortec.ro/en/mq-2-gas-sensor
- Details: https://sigmanortec.ro/en/llms/p/636.md
- Price: 9.73 RON
- Availability: In stock; 1-2 zile
- Reference: 22131 · EAN: 5947120772286
- Specifications: tension: AD; Input Voltage: 5 VDC

MQ-2 gas sensor (reference 22131), powered at 5VDC, used to detect a wide range of gases: GPL, H2, CH4, CO, alcohol, smoke and propane. Provides analog or digital output, covers concentrations of approximately 300 - 1000 ppm, and allows simple monitoring, for example by reading pin A0 and displaying via Serial, suitable for Arduino projects and safety systems.

### MQ-3 Alcohol Ethanol Gas Sensor
- Page: https://sigmanortec.ro/en/mq-3-alcohol-ethanol-gas-sensor
- Details: https://sigmanortec.ro/en/llms/p/637.md
- Price: 15.23 RON
- Availability: In stock; 1-2 zile
- Reference: 22132 · EAN: 5947650793591
- Specifications: tension: AD; Input Voltage: 5 VDC

MQ-3 gas sensor module for detecting alcohol and ethanol vapors, suitable for Arduino projects and safety automation. Supply voltage 5VDC, current draw 150mA. Provides an analog output 0-5V that varies with the detected concentration, plus a digital TTL output with adjustable threshold. Main chips LM393 and ZYMQ, LM393 comparator for simple integration.

### Gas Sensor MQ-4 Methane Natural Gas
- Page: https://sigmanortec.ro/en/gas-sensor-mq-4-methane-natural-gas
- Details: https://sigmanortec.ro/en/llms/p/638.md
- Price: 9.98 RON
- Availability: In stock; 1-2 zile
- Reference: 22133 · EAN: 5945116496291

MQ-4 gas sensor module for detecting methane and natural gas, based on an SnO2 sensor. Power supply 5VDC, 150mA. Detects concentrations between 300-10000ppm. Provides an analog output 0-5V proportional to concentration and a digital TTL output with adjustable threshold. Easy to integrate into Arduino projects via A0 pin reading, suitable for gas leak monitoring systems.

### Gas Sensor MQ-5 natural gas, LPG, coal smoke
- Page: https://sigmanortec.ro/en/gas-sensor-mq-5-natural-gas-lpg-coal-smoke
- Details: https://sigmanortec.ro/en/llms/p/639.md
- Price: 12.63 RON
- Availability: In stock; 1-2 zile
- Reference: 22134 · EAN: 5949260054246

MQ-5 gas sensor for detecting natural gas, LPG and coal smoke, suitable for Arduino projects and safety systems. Power supply 5VDC, consumption approx. 150mA. Provides analog output 0-5V proportional to concentration and TTL digital output for thresholds. Good resistance to alcohol and smoke interference.

### Gas Sensor MQ-6 LPG Propane Butane
- Page: https://sigmanortec.ro/en/gas-sensor-mq-6-lpg-propane-butane
- Details: https://sigmanortec.ro/en/llms/p/640.md
- Price: 14.34 RON
- Availability: In stock; 1-2 zile
- Reference: 22135 · EAN: 5949584258580

MQ-6 gas sensor module for detecting LPG, propane, butane and LNG, suitable for leak monitoring in Arduino projects or industrial systems. Power supply 5VDC, 150mA. Analog output 0-5V proportional to gas concentration and digital TTL output for thresholds. Good resistance to interference from ethanol and smoke, quick integration via analog or digital pin reading.

### Gas sensor MQ-7 Carbon monoxide
- Page: https://sigmanortec.ro/en/gas-sensor-mq-7-carbon-monoxide
- Details: https://sigmanortec.ro/en/llms/p/641.md
- Price: 11.74 RON
- Availability: In stock; 1-2 zile
- Reference: 22136 · EAN: 5947993441395

MQ-7 gas sensor for detecting carbon monoxide, with a measuring range of 10-1000 ppm CO. Power supply 5VDC, approx. 50mA. Provides an analog output 0-5V (voltage proportional to concentration) and a digital TTL output with a threshold adjustable via potentiometer. Requires preheating for stable readings. Can be used with Arduino or standalone.

### MQ-8 Hydrogen Gas Sensor
- Page: https://sigmanortec.ro/en/mq-8-hydrogen-gas-sensor
- Details: https://sigmanortec.ro/en/llms/p/642.md
- Price: 9.34 RON
- Availability: In stock; 1-2 zile
- Reference: 22137 · EAN: 5943947744758

The MQ-8 sensor detects hydrogen and is suitable for Arduino projects and industrial monitoring applications. It operates at 5VDC with low power consumption, features an analog output of 0-5V that varies with the detected concentration, and a digital TTL output for thresholds. It is resistant to interference from ethanol, CO2 and other gases for more stable measurements.

### MQ-9 CO Gas Sensor
- Page: https://sigmanortec.ro/en/mq-9-co-gas-sensor
- Details: https://sigmanortec.ro/en/llms/p/643.md
- Price: 13.79 RON
- Availability: In stock; 1-2 zile
- Reference: 22138 · EAN: 5940764832781

MQ-9 sensor module for detecting carbon monoxide and other combustible gases, suitable for Arduino projects and air quality monitoring systems. Detects 10-1000ppm CO and 10-1000ppm other combustion gases. Power supply 5VDC, approx. 50mA. Analog output 0-5V proportional to concentration and digital TTL output for alarm thresholds.

### Air quality sensor MQ-135
- Page: https://sigmanortec.ro/en/air-quality-sensor-mq-135
- Details: https://sigmanortec.ro/en/llms/p/625.md
- Price: 14.94 RON
- Availability: In stock; 1-2 zile
- Reference: 22139 · EAN: 5944647993200

MQ-135 air quality sensor module, based on SnO2, whose conductivity changes according to pollution level. Detects ammonia, gasoline vapors, smoke and other harmful gases. Power supply 5VDC, current draw about 50mA. Provides an analog output 0-5V for continuous measurement and a digital TTL output for settable thresholds. Easy to integrate with Arduino and other microcontrollers.

### Sensor module BME680, I2C, 3.3V
- Page: https://sigmanortec.ro/en/sensor-module-bme680-i2c-33v
- Details: https://sigmanortec.ro/en/llms/p/2115.md
- Price: 82.62 RON
- Availability: Out of stock
- Reference: 9949 · EAN: 5940934282606
- Specifications: Input Voltage: 3.3 V; Input Voltage Type: “DC” in Romanian can mean **“de ce”**, which translates to **“why”** in English.

BME680 sensor module with I2C communication, 3.3V supply (operating range 1.7V-3.6V). Measures temperature (-40 to 85 °C, ±1.0 °C), humidity (0-100%, ±3%), atmospheric pressure (300-1100 hPa, ±1 hPa) and air quality (VOC). Also supports SPI. Pins: VCC, GND, SCL, SDA, SDO, CS. Suitable for weather stations, automation and IoT projects.