Quest Technologies has developed QUESTemp° II and QUESTemp° III Personal Heat Stress Monitors. The QUESTemp° II is an easy-to-use personal heat stress indicator that monitors an individual's body temperature for indications of the onset of heat stress. The QUESTemp° III is an extremely compact personal heat strain indicator that monitors an individual's heart rate and body temperature for indications of the onset of heat strain. The QUESTemp° II ' III consider the effects of wearing protective clothing and an individual's personal physical condition. Both units are compact and lightweight with audio and/or visual alarms.