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Mike Israni Senior Technical AdvisorManager: National StandardsJuly 30, 2009
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NTSB issued P-01-2 on June 22, 2001 PHMSA should require operators to install
EFVs on all new and replacement service linesAll customer classifications with suitable gas
service conditions included
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Section 9 mandated that PHMSA require EFV installation on new and replacement single family residential service lines operating at ≥ 10 psig continuously throughout the year
PHMSA issued Advisory Bulletin ADB-08-04 Advised gas distribution operators that EFV mandate went into effect
June 1, 2008PHMSA issued NPRM for DIMP which proposed to:
Eliminate 49 CFR 192.383, EFV notification requirement Require EFV for SFR Service Line (Proposed 49 CFR 192.1011 )
Require operators to report the number of EFVs installedRetain exceptions due to operations difficulties
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Data collection Incidents subject to mitigation Additional data requirements
Review recommendation with NTSB Assessment of technical feasibility, cost, risks, safety
Share current EFV technology, availability, and cost data Review EFV utilization: residential, commercial, industrial Identify modifications required for EFV performance stds Identify the effect of EFVs on operations and safety
Changing loads, snap loads, contaminants Service line size and pressure
Compilation of findings
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1557 960 870
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Operators reported 1,108 successful gas flow terminations in response to severe line breaksActuations as % of installed EFVs: 0.044%
EFVs seldom close inadvertentlyFalse closures as % of EFVs: 0.0089%
Reliability data2% of EFVs installed on gas lines that
ruptured failed to function properlyOf the 497 respondents, 3 experienced
failed closures
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EFVs available ≤ 5,500 SCFH, pressures ≤ 1000 psig Dynamic nature of customer load changes could require either
More frequent need to replace EFVs, or Larger service line/EFV in anticipation of future load growth Larger lines/EFVs installed in anticipation of future load
growth could result in greater consequences or failure to close when needed
DIMP rules and damage prevention requirements should reduce incidents and need for EFVs
Data on EFV use beyond SFR is very limited Countries outside of US do not mandate use of EFVs Existing ASTM and MSS standards are based on ensuring
operability at 125 psig inlet pressure