In order to realize high precision detection of survivor life after the earthquake

an intelligent portable life detector is designed.The volume fraction of CO2 is detected by the infrared absorption sensor

and the volume fraction change rate is calculated through interval sampling technique.A fuzzy inference engine is designed based on embedded microprocessor

and the chances of survivors values is reasoning concluded by using the prior knowledge of rescue experts

according to the narrow slot in CO2 volume fraction and rate of change.The information is communicated to the emergency personnel through sound and light alarm and LCD.Experimental analysis shows that the detector fully takes into account the characteristics of CO2 volume fraction changes real time when there are survivors.The prior knowledge of rescue experts is used reasonably

and the precision of search and rescue of survivors in the small space is improved effectively.