• Title/Summary/Keyword: Fire detector

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IR 불꽃화재감지기 개발

  • Gwon, O-Seung;Lee, Bok-Yeong;Park, Sang-Tae
    • Fire Protection Technology
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    • s.29
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    • pp.39-45
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    • 2000
  • All objects emit thermal radiation and this radiation is the basis of the techniques used to detect flames. The usual phenomena occurring in the initial stage of a fire are generally invisible products of a combustion and visible smoke. Liquid or gaseous materials do not undergo a smoldering stage such fires develop very rapidly. Also, the heat generated by the initial flames is usually not sufficient to active a heat detector. In this case the most effective criterion for automatic fire detection is the flame. In fire regulation of korea, the compulsory standard provided that a flame detector shall be installed a place of the attachment hight of detector is higher than 20 m, chemical plants, hangar, refinery, etc.. The result of the research and development are discriminated between a flame and other radiant emitters, developed PZT pyroelectric element is based on the use of photo-voltanic cell, developed IR band-pass filter that only allow a 4.3 radiation wavelength to reach the sensors and developed IR flame detector.

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A Study on the Development of the Photo-electric Single Station Smoke Alarm of Low Power Consumption for Residential Fire Prevention (주택화재 예방을 위한 저소비 전력의 광전식 단독경보형감지기 개발에 관한 연구)

  • Park, Se-Hwa;Cho, Jae-Cheol
    • Fire Science and Engineering
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    • v.24 no.1
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    • pp.46-53
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    • 2010
  • This is a case report of a photo-electric single station alarm for residential fire prevention. The detector was developed for the certification in Japanese market which is more than 100 times bigger than Korean market. A comparison and review for test standard owned by KFI (Korea Institute of Fire Industry & Technology) and JFEII (Japan Fire Equipment Inspection Institute) respectively is also conducted. The detector alarms with a buzzer and an indicating LED. Operating period and time in alarm, low battery and fire situation is stated. The electronics circuit part to reduce its current and the detector's characteristics are described. It is explained that the measured current and experimental result of the battery discharge can meet the 10 years operation.

Optical Properties for Smoke Particles of Fire Sources According to UL 268 (UL 268 화원에 의한 연기입자의 광학적 특성)

  • Jee, Seung-Wook;Lee, Jong-Hwa
    • Fire Science and Engineering
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    • v.28 no.2
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    • pp.9-13
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    • 2014
  • This paper is basic study for development of the photoelectric-type smoke detector that is able to distinguish fire source as well as fire detection. For this subject, Light source and sensor which is normally used for the conventional smoke detector are assembled for the optical chamber. Using 3 type of the test fires (the paper fire, the wood fire, the flammable liquid fire) this paper attempts to find optical properties of each fire. These 3 type of fire are used in the testing of smoke detector according to UL 268 standard. As the result, there are disambiguated between the paper fire and the wood fire in scattering and reason of extinction in the flammable liquid fire is different from that of the paper and the wood fire.

A Study about False Alarm of Automatic Fire Detection System (자동화재 탐지설비의 비화재보 감소방안)

  • Lee, Jong-Hwa;Lee, Chun-Ha;Kim, Shi-Kuk;Kong, Ha-Sung
    • Journal of the Korea Safety Management & Science
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    • v.13 no.1
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    • pp.41-49
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    • 2011
  • The automatic fire detection system is an important facility installed with focusing on minimizing the damage from a fire. This paper presents in the followings as the methods to reduce the false alarm of the automatic fire detection system; first, to prepare for legal standard so that revised legal standard can be applied to the fire fighting property prior to revision; second, to introduce the performance based fire detection protection design in the law based fire protection design; third, to maintain the wiring of worn-out detector; forth, to introduce an evaluation system to the education for the fire warden; fifth, to extend the standard of MTBF(meantime between failure) of the detector; sixth, to extend of installing the analog type detector; seventh, to improve the structure of reset switch.

A Study on the Comparison of Aspirating Smoke Detector and General Smoke Detector Detection Time according to the Fire Speed and Location of Logistics Warehouse through FDS (화재시뮬레이션을 통한 물류창고 화재 속도와 위치에 따른 공기흡입형 감지기와 일반 연기 감지기 감지시간 비교에 관한 연구)

  • SangBum Lee;MinSeok Kim;SeHong Min
    • Journal of the Society of Disaster Information
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    • v.19 no.3
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    • pp.608-623
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    • 2023
  • Purpose: Recently, the number of logistics warehouses has been on the rise. In addition, as the number of such logistics warehouses increases, number of fire accidents also increases every year, increasing the importance of preventing fires in large logistics warehouses. Method: investigated aspirating smoke detectors that are emerging as adaptive fire detectors in logistics warehouses. Then, through fire simulation (FDS), logistics warehouse modeling was conducted to compare and analyze the detection speed of general smoke detectors and aspirating smoke detectors according to four stages of fire growth and three locations of fire in the logistics warehouse. Result: Growth speed in Slow-class fires and Mediumclass fires, the detection speed of aspirating smoke detectors was faster regardless of the location of the fire. However, in Fast-class fires and Ultra-Fast-class fires, it was confirmed that the detection speed of general smoke detectors was faster depending on the location of the fire. Conclusion: It was confirmed that the detection performance of the aspirating smoke detector decreased as the fire growth speed increased and the location of the fire occurred further than the receiver of the aspirating smoke detector. Therefore, even if an aspirating smoke detector is installed in a warehouse that stores combustibles with high fire growth rates, it is judged that an additional smoke detector is attached far away from the receiver of the general smoke detector to increase fire safety.

Fuzzy Measure를 이용한 화재감지기의 기본설계

  • 백동현;김기화
    • Fire Science and Engineering
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    • v.10 no.3
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    • pp.19-28
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    • 1996
  • This paper present the way the fire detector determines whether a fire has broken out or not using the fuzzy measure. This method is based on Dempster's combination rule using the belief measure. The detector indicate a 'Fire'(F) or 'Nonfire'(N) when it determines whether a fire has broken out or not. To determine this, the fuzzy rule is applied in the setting value for the heat and smoke detector which is used. As a result, It is proved that the final decision can be determined more exactly whether a fire has broken out or not in proportion to the frequency of the fuzzy measure and the value of Bel (F).

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Automatic Fire Detector Spacing Calculation for Performance Based Design (성능위주설계를 위한 화재감지기배치의 공학적연구)

  • Park, Dong-Ha
    • Fire Science and Engineering
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    • v.24 no.1
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    • pp.15-23
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    • 2010
  • Placement method for fire detectors prescribed in current fire safety regulation is just about placing a prescribed number of detectors according to the areas. However, this regulation has no scientific basis and standards from foreign countries are just introduced and fire detectors are installed complying with them. There are two standards in designing fire protection systems; Prescriptive-Based Design that follows stipulated regulations like fire safety standards and Performance-Based Design based on engineering knowledge such as fire dynamics, structural dynamics, mechanics of materials, fluid mechanics, and thermo dynamics. Recently, Fire Protection System Construction Business Act was revised so that fire protection systems can be designed using Performance-Based Design method ('05. 8. 4), though the method has not activated until now. In addition, the enforcement decree defines the range for specific objects of fire protection to which Performance-Based Design is applied ('07, 1. 24). At the moment, by manufacturing simulator so that formulas can be introduced and calculated with software in order to install fire detector of automatic fire detection systems keeping optimized distance, comparing the results with the state of fire detector placed according to Performance-Based Design and analyzing them, this study was intended to settle Performance-Based Design method in the future.

A Study on the Improvement for Sensitivity Test of Flame Detectors (불꽃화재감지기의 시험기준 개선에 관한 연구)

  • Baek, Dong-Hyun
    • Fire Science and Engineering
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    • v.28 no.6
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    • pp.58-61
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    • 2014
  • Flame detectors has been used more than heat & smoke detector, because this is more effective to catch fire and ceiling height in spite of high price. For upgrade to flame detector, Compare to national or abroad standard about performance test, sensitivity test, sectioning indoor or outdoor, after service and management. As a result, Europe and America have only sensitivity test, no have not operation test and sectioning indoor & outdoor. In performance test, action is put to focus to credit and durability, Not operation test is to be able to tune the sensitivity to match the environment of the site. Also, we need code about aftercare, quality assurance responsibility and implement special detector institution by Certificate Authority implement.

Study of the Improvement of False Fire Alarms in Analog Photoelectric Type Smoke Detectors (아날로그 광전식 연기감지기 비화재보 개선에 대한 연구)

  • Seo, Byung Keun;Nam, Sang Gu
    • Fire Science and Engineering
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    • v.30 no.5
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    • pp.108-115
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    • 2016
  • Fire detectors play an important role in alerting the related people to the initial stages of fire to protect assets and life. Therefore, the performance in detecting fires in the early stages without the risk of false alarms is important. Owing to a recent revision of the national fire safety standards to install smoke detectors in living rooms used for sleeping, staying, hospitalizing in apartment house/efficiency apartment/lodging facility/medical facility/facility for elderly and young, the application of smoke detectors is increasing. On the other hand, there is lack of research in preventing false alarms. This study improved algorithms to prevent false alarms in analog photoelectric smoke detector's due to sudden dust and better classify pollution and fire signals through a self-compensatory function. Through this study, alternatives are suggested to reduce the number of false alarms of Analog Photoelectric smoke detectors, and prevent financial losses due to false alarms.

A Study on the Response Characteristics Depending on Service Life of Ionization Smoke Detector (이온화식연기감지기의 사용기간에 따른 응답특성 연구)

  • Baek, Won-Don;Kim, Shi-Kuk;Ok, Kyung-Jea;Lee, Chun-Ha;Jee, Seung-Wook
    • Fire Science and Engineering
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    • v.22 no.4
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    • pp.61-64
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    • 2008
  • This paper studied on the response characteristics depending on service life of ionization smoke detector. The experimental samples used ionization smoke detectors (360 EA) for over 5 years which were influenced by environment set up with fire objects. The experimental method performed operate and non-operate test according to 'Type Approval and Technical Regulation of Detector (KOFEIS 0301)', for estimate the response characteristics of ionization smoke detector depending on service life. The results showed that their response characteristics were rapidly decreasing when the longer their using period. Accordingly, it is desirable that ionization smoke detector has to be changed for early fire detection when passed their service life.