Portable Toxic Gas Detector

The portable Toxic Gas Detector is a gas detection instrument that can simultaneously detect the concentration of any 1 to 6 toxic and harmful gases. It will issue an audible, visual, and vibration alarm when any gas concentration exceeds the standard. Temperature and humidity measurement functions can also be added.

This handheld toxic gas detector is portable and convenient for detecting the concentration or leakage of toxic and harmful gases such as carbon monoxide, vinyl chloride, hydrogen sulfide, chlorine, hydrogen cyanide, acrylonitrile, nitrogen dioxide, benzene, ammonia, carbonyl chloride, phosgene, fluorine, hydrogen fluoride, arsine, bromine, germane, and diborane in the environment.

★★★★★

Short delivery time
Better price
Customizable parameters

Features

1. Three display modes freely switchable: simultaneous display of multiple gas concentration values, large-screen display of single gas concentration, or display of single gas concentration changes over a specific time period;

2. Optional high-temperature, telescopic, or non-telescopic gas sampling handles. Extended detection range, suitable for confined space inspections such as equipment pipelines;

3. Operates reliably within -40°C to +70°C ambient temperatures with automatic temperature compensation to eliminate thermal effects on measurements;

4. Supports multiple alarm modes: LOW alarm, HIGH alarm, MAC, PC-STEL, PC-TWA, and other OEL alarm configurations;

5. High-precision gas sensors deliver accurate detection results with minimal deviation. Features rapid leak detection with short warning times and swift response;

6. Features Ex ia IIC T4 Ga intrinsically safe national explosion-proof CNEX certification and IP67 waterproof/dustproof capability, suitable for diverse hazardous and complex operational environments;

7. Features a 6000 mA high-capacity rechargeable battery, enabling the portable toxic gas detector to fully meet continuous gas monitoring requirements throughout an entire workday;

8. Optional wireless data transmission functionality supports multiple protocols including Wi-Fi, ZigBee, Bluetooth, GPRS, RoLa, and 443M.

Specifications

Detected Gases	Any 1-6 toxic and harmful gases (hydrogen sulfide H2S, carbon monoxide CO, nitrogen dioxide NO2, formaldehyde CH2O, chlorine Cl2, hydrogen peroxide H2O2, methanol CH4O, sulfur dioxide SO2, ammonia NH3, hydrogen fluoride HF, volatile organic compounds VOCs, and combustible gases Ex) Optional: Detects optional temperature, wind direction, noise, wind speed, humidity, atmospheric pressure, PM2.5, PM10, etc.
Range and resolution	H2S: 0-100ppm, 0.01ppm, high-performance electrochemicals
	CO: 0-500ppm, 0.1ppm, high-performance electrochemicals
	NO2: 0-100ppm, 0.01ppm, high-performance electrochemicals
	CH2O: 0-20ppm, 0.01ppm, high-performance electrochemicals
	CL2: 0-20ppm, 0.01ppm, high-performance electrochemicals
	H2O2: 0-50ppm, 0.01ppm, high-performance electrochemicals
	CH4O: 0-100ppm m: 0.01ppm, high-performance electrochemical
	SO2: 0-100ppm, 0.01ppm, high-performance electrochemical
	NH3: 0-100ppm, 0.01ppm, high-performance electrochemical
	HF: 0-10ppm, 0.001ppm, high-precision electrochemical
	VOC: 0-100ppm, 0.01ppm, high-precision PID photoionization
	Ex.: 0-100%LEL, 0.1%LEL, industrial-grade catalytic combustion
	Other gases, ranges, principles, and resolutions can be customized.
Detection Method	Built-in pump suction, flow rate 500 ml/min
Display Method	2.5-inch 320*240 high-definition color screen display
Detection Accuracy	≤±2%F.S (higher precision can be customized)
Alarm Method	Sound + flash + vibration + screen alarm, alarm off optional
Response Time	T90≤20 seconds
Operating Power Supply	3.7VDC, 6000mA high-capacity polymer rechargeable battery
Data Storage	Standard 100,000 data entries capacity, larger capacity can be customized
Communication Interface	USB (charging and communication), RS232, infrared communication, automatic identification
Protection Functions	IP67 waterproof and dustproof rating
Explosion-proof Functions	Intrinsically safe, Ex ia ⅡC T4 Ga explosion-proof rating
Dimensions	195×77×46mm (L×W×H)
Product Weight	500g

Product Configuration

Standard Accessories	USB charger (with data cable), pump-suction toxic gas detector, instruction manual, humidity and dust filter, certificate of conformity, premium aluminum alloy instrument case.
Optional Accessories	Lanyard, multiple humidity/dust filters, high-temperature/high-humidity pretreatment system, 1.2 m extendable sampling handle (1-10 m hose, standard length 1 m), high-temperature sampling cooling filter handle, CD (host computer communication software), external miniature wireless infrared printer, temperature/humidity measurement function.
Temperature Measurement (Optional)	-40°C to +120°C, accuracy 0.5°C.
Humidity Measurement (Optional)	0-100%RH, accuracy 3%RH.
Wireless Transmission (Optional)	Bluetooth, 443MHz, ZigBee, GPRS, WiFi, RoLa, etc.

Common Toxic Gases:

No.	Name	No.	Name	No.	Name
1	Carbon monoxide	2	Vinyl chloride	3	Hydrogen sulfide
4	Chlorine	5	Hydrogen cyanide	6	Acrolein
7	Nitrogen dioxide	8	Benzene gas	9	Ammonia
10	Carbonyl chloride	11	Phosgene	12	Fluorine
13	Hydrogen fluoride	14	Arsenic hydrogen	15	Bromine
16	Hydrogen bromide	17	Germanane	18	Boron trifluoride
19	Aniline	20	Pyridine	21	Acetone
22	Iodine gas	23	Methyl bromide	24	Thionyl chloride
25	Ethylene oxide	26	Phosphine	27	Hydrazine
28	Sulfur hexafluoride	29	Dichloroethylene	30	Sulfur dioxide

Note: For other unlisted toxic and harmful gases, please consult us.

Toxic Gas Detector Working Principle

The principles behind toxic gas detection are diverse, primarily including electrochemical principles, photoionization detection (PID), and catalytic combustion. Among these, electrochemical sensors are the most widely used.

Electrochemical sensors utilize electrochemical reactions to detect the concentration of toxic gases. When a gas reacts with an electrolyte in the sensor, it generates a change in current or potential. By measuring these changes, the gas concentration can be determined. Electrochemical sensors offer advantages such as high sensitivity, fast response, and good selectivity, and are commonly used to detect: carbon monoxide (CO), hydrogen sulfide (H₂S), sulfur dioxide (SO₂), nitric oxide (NO), nitrogen dioxide (NO₂), ammonia (NH₃), chlorine (Cl₂), hydrogen cyanide (HCN), and hydrogen chloride (HCl), among others.

Pay attention to the concentration measurement range of the detection instrument.

Various toxic and harmful gas detectors have their fixed detection ranges. Only by completing measurements within this range can the instrument guarantee accurate readings. Prolonged measurements outside the detection range may cause permanent damage to the sensor.

For example, an LEL detector, if accidentally used in an environment exceeding 100% LEL, may completely burn out the sensor. Similarly, toxic gas detectors will be damaged if used at high concentrations for extended periods. Therefore, if the instrument issues an over-limit signal, the measurement circuit should be immediately shut down to ensure sensor safety.

Diffusion vs. Pump-Suction

When choosing a toxic gas detector, you will encounter the choice between diffusion and pump-suction types.

Diffusion gas detectors detect the concentration of toxic and harmful gases in the environment through gas diffusion. When the detected concentration is too high or too low, an audible and visual alarm is emitted via an alarm light on the detector, prompting personnel in the environment to take appropriate action.

Pump-suction gas detectors actively deliver gas into the detector by using a gas pump connected to a gas pipe to continuously draw gas into the instrument. This device actively extracts air to detect the presence of toxic and harmful gases in the environment, monitoring them in real time inside the instrument. When the concentration of toxic or harmful gases exceeds the limit, an alarm is triggered immediately to alert personnel in the environment.

Diffusion-type gas detectors are suitable for well-ventilated spaces and industrial settings with relatively uniform gas distribution. Pump-suction gas detectors are suitable for confined spaces, underground pipe corridors, storage tanks, and other conditions where natural gas circulation is difficult.

Technical Support

A toxic gas is one that can cause injury, illness, or death through a chemical reaction or interference with the body’s biological processes, often at very low concentrations (measured in parts-per-million, or ppm). A combustible or flammable gas is one that can ignite and burn or explode when mixed with air and exposed to an ignition source. Its danger is primarily measured as a percentage of its Lower Flammable Limit (%LFL). Many gases, like hydrogen sulfide, can be both toxic at low levels and flammable at much higher concentrations.

The manufacturer’s recommendation is the primary guide, but a typical schedule for a full calibration is every 3 to 6 months. However, the frequency should be increased if the device is used in a harsh environment, has been dropped, or if bump tests indicate a potential issue. A bump test, which simply verifies sensor and alarm function, should be performed before each day’s use.

Cross-sensitivity occurs when a gas sensor designed to detect a specific target gas shows a response to a different, interfering gas. For example, an electrochemical carbon monoxide (CO) sensor might show a small positive reading when exposed to hydrogen (H₂). Reputable manufacturers provide cross-sensitivity charts that quantify these effects, allowing users to better interpret readings in environments with mixed gases.

A zero reading is the desired state, but it doesn’t confirm the detector is functional. The only way to be certain is to perform a bump test by briefly exposing the sensor to a known concentration of the target gas to ensure it responds and the alarms activate. This simple check verifies that the sensor is not dead or blocked and that the device is capable of warning you.

No, a single detector with one sensor cannot measure all gases. Different gases require different sensor technologies for detection. However, multi-gas detectors are available that can house several different sensors (e.g., an electrochemical sensor for H₂S, another for CO, an IR sensor for CO₂, and a PID for VOCs) within a single instrument, allowing it to monitor for multiple, distinct hazards simultaneously.

Intrinsic Safety (IS) is a design principle and certification for electronic equipment used in hazardous locations where flammable gases or dusts may be present. An IS-certified gas detector is designed to operate at such low energy levels that it is incapable of producing a spark or hot surface that could ignite the surrounding atmosphere, even under fault conditions.

These are all units of concentration. PPM (parts-per-million) and PPB (parts-per-billion) are used for measuring the very low concentrations typical of toxic gases (1 ppm is one part gas per one million parts air). % LEL (percent of the Lower Explosive Limit) is used for flammable gases. The LEL is the minimum concentration of a gas in air that can ignite. A reading of 100% LEL means the gas is at its explosive threshold; a reading of 10% LEL means the concentration is at 10% of that threshold.

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Users should wear appropriate protective masks and follow proper procedures when using the Portable Toxic Gas Detector, especially in workplaces where there is a known possibility of leakage or accumulation of one or more toxic or hazardous gases.

Additionally, when using the handheld toxic gas detector, optional accessories such as water vapor/dust filters, high-temperature or telescopic sampling probe handles should be selected based on the actual working conditions and customer needs. Additional functions include fall detection alarms, wireless transmission, linkage alarms, and wireless printing. For details, please consult a Sino-Inst sales engineer!

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