Performance of a fire detector based on a compact laser spectroscopic carbon monoxide sensor

Area of Science:

• Engineering
• Analytical Chemistry
• Environmental Science

Background:

• Traditional smoke detectors suffer from high false alarm rates.
• Existing point fire detection technologies have limitations in sensitivity and specificity.
• Carbon monoxide (CO) is a key indicator of combustion processes.

Purpose of the Study:

• To evaluate the suitability of a miniaturized tunable diode laser spectroscopy (TDLS) sensor for fire detection.
• To assess the performance of a vertical-cavity surface-emitting laser (VCSEL)-based CO sensor under realistic fire conditions.
• To investigate the cross-sensitivity of the sensor to common interfering substances.

Main Methods:

• Development and utilization of a miniaturized TDLS sensor incorporating a VCSEL.
• Implementation of an inherent calibration scheme with reference gas.
• Conducting fire-detection experiments according to European standard EN54, including Class C fires.
• Testing cross-sensitivity with substances like cigarette smoke, hairspray, and aerosols.

Main Results:

• The TDLS-based CO sensor effectively resolved CO generation from all tested Class C fires.
• Cross-sensitivity to other substances was minimal, with low false CO responses observed only under direct application.
• The sensor demonstrated a significantly lower false alarm rate compared to conventional smoke detectors.
• The miniaturized size and inherent calibration scheme enhance its applicability.

Conclusions:

• The VCSEL-based TDLS sensor exhibits sufficient performance for reliable fire detection.
• This technology offers advantages such as fail-safe operation and low cross-sensitivity.
• The sensor is well-suited for both household and industrial fire detection applications, overcoming limitations of current technologies.