HKIE CPD Training Course (II)fe.hkie.org.hk/FireDigest/Document/Images/... · HKIE CPD Training...
Transcript of HKIE CPD Training Course (II)fe.hkie.org.hk/FireDigest/Document/Images/... · HKIE CPD Training...
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HKIE CPD Training Course (II)9 July 2009
Organization by
The Hong Kong Institution of Engineers – Fire Division
Co-organized by the Association of Registered Fire Service
Installation contractors of Hong Kong Ltd (FSICA)
Clean Agent Extinguishing George Ip – Senior Technical Specialist , 3M APAC
Origin and Development of NFPA 2001The Technical Committee on Halon Alternative Protection Options was organized in 1991 and immediately started work to address the new total flooding clean agents that were being developed to replace Halon 1301.
A need existed for an explanation of how to design, install, maintain, and operate systems using these new clean agents, and NFPA 2001 was established to address this need. The 1994 edition was the first edition of NFPA 2001. This standard was revised in 1996, 2000, and 2004. In January 2005, the technical committees responsible for NFPA 12, NFPA 12A, and NFPA 2001 were combined into the Technical Committee on Gaseous Fire Extinguishing Systems to better address and resolve issues among those documents. This action is intended to facilitate correlation and consistency as requested by the U.S. Environmental Protection Agency.The 2008 edition has added requirements for local application systems.
NFPA® 2001Standard on Clean Agent Fire Extinguishing Systems 2008 Edition
3.3.6 Clean Agent. Electrically nonconducting, volatile, or gaseous fire extinguishantthat does not leave a residue upon evaporation.
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HALON 1211
−3.7 °CBoiling point−159.5 °CMelting point1.799 g/cm3Density165.36 g/molMolar massCBrClF2Molecular formula
Properties
Bromotrifluoromethane
1434 kPa (20 °C)Vapor pressure
1.86log P
0.03 g/l (20 °C)Solubility in water
-57.75 °CBoiling point
−167.78 °CMelting point
1.538 g/cm3 (−58 °C)
Density
Colorless gasAppearance
148.91 g mol−1Molar mass
CBrF3Molecular formula
Properties
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Safety Margin for Flooding Agents
lethal @ design conc.<5%30 - 75%CO2
0 - 13%43%38 - 43%Inert Gas
3 - 20%9%7.5 - 8.7%HFC-227ea
---7.5%8.7-12.1%HFC-125
67 - 150%10%4 - 6%FK-5-1-12
Safety MarginNOAEL*Use Conc.Agent
* No Observable Adverse Effect Level
Easy to be seen , easy to be detected
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Cylinders needed for typical Class A system
Halon 1301 HFC-227ea FK-5-1-12 CO2 Inert Gas
ISO 10460:2005(E)Gas cylinders Welded carbon-steel gas cylinders Periodic inspection and testing
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滅火器變飛彈工人斷臂事件
嘉利大廈滅火器轟斷工人手臂根據 2004 年 6 月 29 日《明報》報道:曾發生五級大火、
現正拆卸的油麻地嘉利大廈,昨日發生罕見工業意外。一名工人在地盤 3 樓工作期間,一個盛載滅火劑的近 100 磅重高壓氣樽,疑氣體大量洩漏,如火箭般急速旋轉一飛 天,彈到對面大廈 16 樓,撞穿冷氣機鐵架後反彈回嘉利地盤。氣樽「發射」之際,工人被氣樽打斷左前臂重傷,另一名男途人亦被氣樽擊落的角鐵所傷送院。【右圖來源:《太陽報》網站】
發生意外的嘉利大廈,於 1996 年因電梯維修引致五級大火,21 小時後救熄,奪去 40 人性命,80 多人受傷。慘劇後,嘉利大廈的發展一直被凍結,至去年才以強制拍賣形式出售,計劃重建成 8 至 9 層高的銀座式商場。釀成意外的「炮彈」氣樽,4 呎高、直徑 1 呎、重 97 公斤,盛載滅火氣體「Halon 1301」。地盤工人稱,大廈由 15 樓開始清拆,至日前拆至 3 樓才發現該氣樽。【左圖來源:《太陽報》網站】
http://www.plkchc.edu.hk/~chem/chemsir/dailylife/halon_1301_extinguisher_break_arm.htm
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0000Ozone Depletion Potential
12000350034001Global Warming Potential (100 yr ITH)
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HFC-227ea
260
HFC-23
290.014Atmospheric Lifetime (years)
HFC-125FK-5-1-12Properties
Halocarbon Clean Extinguishing Agents
Environmental Properties Comparison
Naturally occurring compounds
HFCs
PFCs
HFEs
FK-5-1-121C2F5C(O)CF(CF3)2
55C4F9OC2H5 (HFE-7200)320C4F9OCH3 (HFE-7100)
22,200SF6
8,600 - 9,000C3F8, C4F10, C6F14
11,900C2F6
12,000CF3H (HFC-23)3,500CF3CFHCF3 (HFC-227ea)1,300CF3CH2F (HFC-134a)
23CH4
296N2O1CO2
GWP (100 Yr ITH)Compound
GWP of Various Compounds
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Global Regulatory UpdateThe concern rests with the environmental impact of some chemical clean agents in terms of:
– Atmospheric Lifetime (ALT).– Global Warming Potential (GWP).– Contributions to Greenhouse Gases (GHG) from the emissions of
hydrofluorocarbons (HFCs).– Basket”: Four gases and two groups are regarded collectively with
respect to achieving Kyoto Protocol 京都協議emissions goals.• Carbon dioxide (CO2), Methane (CH4), Nitrous oxide (N2O), Sulphur
hexafluoride (SF6)• Hydrofluorocarbons (HFCs), Perfluorocarbons (PFCs),
– Kyoto Protocol Introduced 1997• Reduce Emission of Green House Gases• HFC’s Included on the List!
– In the 1997 Kyoto protocol ratified in 2005 is a “related legal instrument”and was adopted by consensus at the third meeting of the Conference of the Parties (COP 3) to the UNFCC.
– Carbon Equivalence: CO2 is the reference gas. Emissions of other gases expressed in terms of a carbon equivalent (CE) basis.
Environmental Status• Halon 1301 must be removed in Europe
by December 2003 and destroyed• No removal requirement in US currently• HFCs are under attack environmentally
due to GWP
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3500
0.0
HFC-227ea
29.0650.014Atmospheric Lifetime (years)
340069001Global Warming Potential (GWP)*
0120.0Ozone DepletionPotential (ODP)
HFC-125Halon 1301FK-5-1-12 Properties
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• Denmark, Switzerland, & Austria – HFCs banned for fire protection
• Norway – Enacted tax on imports of HFCs• Europe – HFCs should only be used when no
other agent is technically feasible. Proposals include reporting of use of HFCs
• Australia – Currently reviewing HFC use in fire protection
Environmental Status
Global Regulatory Update-AmericaPossible Approaches Being Considered
for Fire ProtectionCARB Sept, 2007
“By 2012,require that all new total flooding fire suppressant systems use fire suppressants with a GWP below a specified threshold.”“That existing total flooding fire suppressant systems enhance inspections of or replace systems using substances with a GWP above a specified threshold….”