• Title/Summary/Keyword: Fire alarm

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Structural Reliability Analysis of Automatic Fire Detectors for Reduction of False Alarms (화재감지기의 오보 감소를 위한 구조 신뢰도 분석)

  • 김주홍;임현교
    • Journal of the Korean Society of Safety
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    • v.8 no.1
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    • pp.6-12
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    • 1993
  • Now it is reported that there are many companies and factories which confront to the problem of false alarm in Automatic Fire Detecting System (AFDS). Though an AFDS is a high-priced and very important device in detecting a fire. the problem degrades the reliability and utility, eventually faith. of the system. This is a research concerned about the problem of false alarm of fire detectors in an AFDS. Structure of detectors was modeled up as a general K out-of n system. and reliability characteristics including false alarm rate and missed alarm rate, are derived from it. For decision of an optimal structure of detectors. preliminary analysis on various criteria is accomplished. It is concluded that appropriate modification of a detector with plural sensors may increase the system reliability and decrease the false alarm rate.

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A Study on the appliance of performance based design to the automatic fire alarm system in clean room facility (클린룸 자동화재탐지설비의 성능위주 방재설계 적용에 관한 고찰)

  • Kim, Dong-Sung;Hwang, Cheol-Seung;Lee, Sang-Gon;Cho, Cheol-Won;Lee, Te-Shik
    • 한국방재학회:학술대회논문집
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    • 2007.02a
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    • pp.513-517
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    • 2007
  • This study is to establish the appliance model for the automatic fire alarm system in clean room within the framework of the performance based design. Because of the environmental and dimensional characters of clean room, this space is exposed to fire and toxic damage, so it is very important to notify the occupants of these dangerous situations.

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A Study on the Development of Fire Alarm System with Evacuation Lighting and Voice Alarm Functions (피난조명 및 음성경보 기능을 내장한 화재경보시스템 개발에 관한 연구)

  • Lee, Gun-Ho;Choi, Su-Gil;Kim, Si-Kuk
    • Fire Science and Engineering
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    • v.32 no.4
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    • pp.25-34
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    • 2018
  • This study investigated the development of a fire alarm system with evacuation lighting and voice alarm functions. The performance of a fire detector and system with independently built-in evacuation lighting and voice alarm functions was confirmed for early recognition of fire and to allow visibility of the evacuation route in the event of fire. This new system satisfied model recognition and product testing technological standards with 1.62 lx average illumination, 89.7 dB average sound and 86.1 dB average voice. From additionally testing the evacuation performance of this new system, it was confirmed that the evacuation time decreased by 63.08% to 67.82% under the experimental conditions compared to conventional systems. The new system can minimize fire damage by setting off voice alarms to prevent failure of fire recognition and by flashing emergency lighting to secure the minimum required visibility range for evacuation. Therefore, it is considered that it will be utilized as a fire alarm system with appropriateness and usefulness by considering people with hearing or visual impairment.

Beliefs of University Employees Leaving During a Fire Alarm: A Theory-based Belief Elicitation

  • Christopher Owens;Aurora B. Le;Todd D. Smith;Susan E. Middlestadt
    • Safety and Health at Work
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    • v.14 no.2
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    • pp.201-206
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    • 2023
  • Background: Despite workplaces having policies on fire evacuation, many employees still fail to evacuate when there is a fire alarm. The Reasoned Action Approach is designed to reveal the beliefs underlying people's behavioral decisions and thus suggests causal determinants to be addressed with interventions designed to facilitate behavior. This study is a uses a Reasoned Action Approach salient belief elicitation to identify university employees' perceived advantages/disadvantages, approvers/disapprovers, and facilitators/barriers toward them leaving the office building immediately the next time they hear a fire alarm at work. Methods: Employees at a large public United States Midwestern university completed an online cross-sectional survey. A descriptive analysis of the demographic and background variables was completed, and a six-step inductive content analysis of the open-ended responses was conducted to identify beliefs about leaving during a fire alarm. Results: Regarding consequence, participants perceived that immediately leaving during a fire alarm at work had more disadvantages than advantages, such as low risk perception. Regarding referents, supervisors and coworkers were significant approvers with intention to leave immediately. None of the perceived advantages were significant with intention. Participants listed access and risk perception as significant circumstances with the intention to evacuate immediately. Conclusion: Norms and risk perceptions are key determinants that may influence employees to evacuate immediately during a fire alarm at work. Normative-based and attitude-based interventions may prove effective in increasing the fire safety practices of employees.

The Analysis of Evacuation Safety by Smoke Alarm in Housing Fire (주택형화재경보기 작동에 따른 피난안전해석)

  • Choi, Young-Sang;Jeon, Heung-Kyun;Bak, Yeul-Sun
    • Fire Science and Engineering
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    • v.25 no.6
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    • pp.73-82
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    • 2011
  • This study was performed to analysis the influence of smoke alarm detector on evacuation safety in housing fire. The analysis was conducted by CFAST fire simulation program and building EXODUS evacuation program. The effects of the earlier response time on evacuation safety were investigated by using evacuation simulation program with several steps of different response time and smoke alarm activation time for 4 occupants. The smoke detecter was activated 37.1 second after fire. The first two mortuary were occurred for 170 seconds of response time at the end of living room near exit. But for the 37.1 seconds of response time 4 occupants evacuated safely. From this study, the fire alarm detector is more important for safety evacuation in housing fire.

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.

Embodiment of Firewall Block for Safety in the Cave (동굴 공간의 안전과 방재차단벽)

  • Kim, Bo-Su;Kim, Kang-Won;Kim, Tae-Hwan;Park, Jung-Ho;Lee, Yung-Jae;Soh, Dea-Wha
    • Journal of the Speleological Society of Korea
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    • no.87
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    • pp.8-13
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    • 2008
  • The automatic firewall block and fire alarm system was embodied by using gas circuit and wireless communication equipment, using a smoke sensor (ST-QA1A) and RF Module. OR-CAD was also used for testing circuit system and experiment circuit after assembling circuit. As a result in experiment, the gas sensor detected well an imaginary smoke and worked reliably for driving action of firewall block motor and wireless warning alarm. Through the smoke sensitive perception from the fire, the warning alarm and the preventing fire propagation from the specific closed region were verified reliably. The gas sensor and RF module for firewall and fire alarm system were actually available.

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.

Development of a Novel Real-Time Monitoring System Algorithm for Fire Prevention (화재예방을 위한 실시간 모니터링 시스템의 알고리즘 개발)

  • Kim, Byeong-Jo;Kim, Jae-Ho
    • Journal of the Korean Society of Safety
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    • v.29 no.5
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    • pp.47-53
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    • 2014
  • Despite the automatic fire alarm system, according to the national fire data system of national emergency management agency, the fires account for 40,932 incidents, 2,184 injuries and about 430 billion won in property losses in 2013. Since the conventional automatic fire alarm system has several weaknesses related to electrical signal such as noise, surge, lighting, etc. Most fires are mainly caused by electrical faults, mechanical problem, chemical, carelessness and natural. The electrical faults such as line to ground fault, line to line fault, electrical leakage and arc are one of the major problems in fire. This paper describes the development of a novel real-time fire monitoring system algorithm including fault detection function which puts the existing optic smoke and heat detectors for fire detection with current and voltage sensors in order to utility fault monitoring using high accuracy DAQ measurement system with LabVIEW program. The fire detection and electrical fault monitoring with a proposed a new detection algorithm are implemented under several test. The fire detection and monitoring system operates according to the proposed algorithm well.