BH-4A portable multi-gas detector could detect combustible gas, O2 and other two types toxic gases continuously and simultaneously. It is widely used in the area where explosion-proof is required or toxic gas leaks, like underground channels or mining industry, so as to protect the workers' life and avoid damage on the relevant equipments.

| Target Gas | Range | Low alarm | High alarm | Resolution |
| EX | (0-100)%LEL | 20%LEL | 50%LEL | 1%LEL |
| H2S | (0-100)ppm | 10ppm | 35ppm | 1ppm |
| CO | (0-1000)ppm | 50ppm | 150ppm | 1ppm |
| O2 | (0-30)%vol | 19.5%vol | 23.5%vol | 0.1%vol |
Other gases needed, please contact us
| Gas sampling method | Natural diffusion |
| Detecting gas | Combustible gas, H2S, CO, O2 |
| Accuracy | ≤±5%FS |
| Response Time | T90<30s |
| Indication | LCD displays real-time and system status; LED, audio and vibration alert for gas leakage, fault and low voltage. |
| Working environment | -20℃~50℃℃, <95%RH (no dew) |
| Power Source | DC3.7V Li-on battery, 1800mAh |
| Explosion-proof grade | Exib IIB T3 Gb |
| Charging time | 6h-8h |
| Working time | ≥8h continuously (without alarming) |
| Gas Sensor Life | 2 years |
| Dimensions | 130*67*30mm |
| Weight | 400g |