[Federal Register: March 10, 2008 (Volume 73, Number 47)]
[Notices]               
[Page 12796]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr10mr08-119]                         

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DEPARTMENT OF TRANSPORTATION

Pipeline and Hazardous Materials Safety Administration

[Docket No. PHMSA-RSPA-2004-19856]

 
Pipeline Safety: Dangers of Abnormal Snow and Ice Build-Up on Gas 
Distribution Systems

AGENCY: Pipeline and Hazardous Materials Safety Administration (PHMSA), 
DOT.

ACTION: Notice; Issuance of Advisory Bulletin.

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SUMMARY: Recent events on natural gas distribution system facilities 
appear to be related to either the stress of snow and ice or 
malfunction of pressure control equipment due to ice blockage of 
pressure control equipment vents by ice. This advisory bulletin advises 
owners and operators of gas pipelines of the need to take steps to 
prevent damage to pipeline facilities from accumulated snow or ice.

FOR FURTHER INFORMATION CONTACT: Alan Mayberry at (202) 366-5124, or by 
e-mail at alan.mayberry@dot.gov.

SUPPLEMENTARY INFORMATION: 

I. Background

    The accumulation of snow and ice increases the potential for damage 
to meters and regulators and other pipeline facilities. Several 
accidents occurring during the winter of 2007/2008 on natural gas 
distribution system facilities appear to be related to either the 
stress of snow and ice or malfunction of pressure control equipment due 
to ice blockage of pressure control equipment vents. Exposed piping at 
metering and pressure regulating stations, at service regulators, and 
at propane tanks, are at greatest risk. Damage may result from the 
stresses imposed by the additional loading of the snow or ice. Damage 
to facilities may also result from the impact of snow or ice falling 
from roofs, or ice forming in or on regulators preventing their proper 
operation, or shoveling snow from roofs to protect dwellings from 
abnormal snow accumulation.

II. Advisory Bulletin (ADB-08-03)

    To: Owners and Operators of Petroleum Gas and Natural Gas 
Facilities in Areas Subject to Heavy Snowfall or Abnormally Icy 
Weather.
    Subject: Dangers of Abnormal Snow and Ice Build-up on Gas 
Distribution Systems.
    Purpose: To inform owners and operators of the need (1) to monitor 
the potential impact of excessive snow and ice on these facilities; and 
(2) to inform the public about possible hazards from snow and ice 
accumulation on regulators and other pipeline facilities.
    Advisory: PHMSA is advising operators of gas pipeline facilities, 
regardless of whether those facilities are regulated by PHMSA or state 
agencies, to consider the following steps to address the safety risks 
from accumulated snow and ice on pipeline facilities:
    1. Notify customers and other entities of the need for caution 
associated with excessive accumulation and removal of snow and ice. 
Notice should include the need to clear snow and ice from exhaust and 
combustion air vents for gas appliances to prevent accumulation of 
carbon monoxide in buildings or operational problems for the combustion 
equipment.
    2. Pay attention to snow and ice related situations that may cause 
operational problems for pressure control and other equipment.
    3. Monitor the accumulation of moisture in equipment and snow or 
ice blocking regulator or relief valve vents which could prevent 
regulators and relief valves from functioning properly.
    4. The piping on service regulator sets is susceptible to damage 
that could result in failure if caution is not exercised in cleaning 
snow from around the equipment. Where possible, use a broom, instead of 
a shovel to clear snow off regulators, meters, associated piping, 
propane tanks, tubing, gauges or other propane system appurtenances.
    5. Remind the public to contact the gas company or designated 
emergency response officials if there is an odor of gas present or if 
gas appliances are not functioning properly. Also remind the public 
that, if there is a gas or propane odor, occupants should leave the 
residence immediately and contact their gas company, propane operator 
or designated emergency response officials.

    Authority: 49 U.S.C. chapter 601; 49 CFR 1.53.

    Issued in Washington, DC on March 5, 2008.
Jeffrey D. Wiese,
Associate Administrator for Pipeline Safety.
[FR Doc. 08-999 Filed 3-6-08; 2:18 pm]

BILLING CODE 4910-60-P