Abstract: An early stage fire detecting apparatus is arranged such that a fire state is discriminated based on a fire probability output from a signal processing network. The fire probability being prepared in such a manner that outputs from a high sensitivity smoke sensor SS and a smell sensor NS, from which responses can be obtained at the early stage of a fire, are subjected to signal processing. Fire information composed of a value at a given moment of smoke and a difference indicating the increase or decrease of the value at a given moment of the smoke and a value at a given moment of smell and a difference indicating the increase or decrease of the value at a given moment of the smell are input to the signal processing network. The signal processing network outputs the above fire probability based on a table (RAM12) defining a fire probability to be obtained from the above fire information and weighting values (RAM13).

Abstract: A fire monitoring system detects a plurality of types of detection information using a plurality of fire phenomenon detectors for detecting physical quantities caused by fire phenomena or using a plurality of detectors each including at least one fire phenomenon detector and at least one environment detector provided in association with the fire phenomenon detector. The plurality of types of detection information undergo consolidated signal processing for obtaining one or more types of fire information for realizing fire monitoring.

Abstract: A fire alarm system discriminates the presence of a fire using plural likelihood ratio functions respectively associated with plural fire related phenomenon. At least one fire related condition, for example, a temperature level, a smoke density or a gas concentration, of a detected area is detected. Data denoting plural fire related phenomenon are generated based on the at least one fire related condition. The data of each fire related phenomenon is applied to a respective likelihood ratio function defining a relation between the value of the fire related phenomenon and the value of a fire likelihood ratio. The fire likelihood ratio defines a relative probability of a fire attributable to the value of the respective fire related phenomenon. Plural fire likelihood ratio values are obtained according to processing rules, and a centroid value is obtained based on the plural fire likelihood ratio values. A fire is discriminated based on the centroid value.

Abstract: A fire alarm system employs a neural network for obtaining one or more types of fire related information values. A plurality of detection information values are time-serially collected from plural fire phenomenon detectors. The detection information values are signal processed such that a weighting coefficient is assigned thereto in accordance with a relative significance of the detection information value to the desired fire related information value. The various weighting coefficients are stored in advance in a memory. The weighting coefficients stored are established so that the fire related information value for a particular set of detection information values approximates a desired fire related information value.

Abstract: A fire detector is equipped with a sensor which detects physical quantities such as heat, light or smoke and which, in particular, stores the time when the fire detector responds or generates an alarm and also stores the output level of the sensor at such time and displays these stored data whenever required. It also stores successive output levels of the sensor at each of a series of predetermined time intervals along with the respective time values until the fire detector generates an alarm and displays these stored data whenever required.

Abstract: A sensor for detecting low concentrations of silane gas in air and a process for making the sensor are disclosed. The sensor comprises a silane-sensitive element and a heater to heat the element to 200.degree.-400.degree. C. The element comprises an electrode-equipped alumina porcelain tube coated with a mixture of SnO.sub.2, SbOCl, and Pt. The tube is calcined in air or in an oxidized antimony atmosphere at 600.degree.-850.degree. C. and is exposed to a silane atmosphere at 150.degree.-850.degree. C. to stabilize its properties.

Abstract: An element for selectively sensing carbon monoxide which is capable of sensing a lower concentration of CO in a quicker response time at ordinary temperatures without the need of heating the element with better SN and low temperature dependence.