Dual-band infrared light detection for fire alarm. Sensitive to flame from material containing carbon. Suitable for fire starting from flame in large indoor or outdoor areas. Addressable (connecting fire alarm control panel) and non-addressable (through relay contact) working modes optional. Flame-proof. Applicable to either commercial or hazardous industrial areas, such as explosive Zone 1 and 2, and Zone 21 and 22 with flammable dust.