EH-91-4 Cold Weather Protection
ENVIRONMENT, SAFETY & HEALTH
BULLETIN
Assistant Secretary for U.S. Department of Energy
Environment, Safety, & Health Washington, D.C. 20585
DOE/EH-0213 Issue No. 91-4 October 1991
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COLD WEATHER PROTECTION
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BACKGROUND
Approximately forty-five occurrences reported in December 1990 were directly
related to cold weather damage, and, by mid-March 1991, eight more
occurrences related to cold weather had been reported at DOE facilities.
Nearly all of the cold weather damage reported at DOE facilities could have
been prevented if an active cold weather protection program had been
established and followed.
Cold weather damage most often occurs in exposed, out-of-the-way areas of the
facility during weekends or other shutdown periods. Failure to identify
areas likely to be susceptible to cold weather damage and improper
maintenance (e.g., doors, windows, or ventilators being left open, as well as
broken windows, cracks, loose siding, or similar defects in building
maintenance) also contribute to cold weather damage. Therefore, it is
essential to:
o Establish a schedule for preparing the facility prior to the cold weather
season.
o Establish a weather watch with written procedures for alerting management
and maintenance personnel. Procedures should be as "automatic" as possible,
and should authorize certain actions at specific temperatures (actual or
forecasted).
o Arrange for watch service and maintenance personnel to be available during
expected cold snaps.
o Develop procedures for repairing or replacing damaged equipment and safely
restoring it to service.
COLD WEATHER PROGRAMS FOR FIRE PROTECTION SYSTEMS
Burst pipes, frozen water lines, and cracked sprinkler heads in fire
protection systems are the most frequently reported problems during cold
weather. One DOE facility recently reported 20 failures of their fire
protection system because of cold weather problems. Expensive repairs to the
system, facility buildings, and equipment may be required as a result of such
failures. More important, however, are the facility's vulnerability to fire
and the increase in potential worker hazards.
Recommendations
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1. Maintain extra heat during periods of extreme cold, especially during idle
periods, to keep the sprinkler piping from freezing. Check the heating
system to ensure that it is delivering sufficient heat to all areas,
particularly at night.
2. Search for isolated drafts or air leaks, particularly in infrequently
visited areas and in spaces where sprinkler pipes are installed. Look
specifically for places where cold air could enter and eliminate even small
openings. Keep all doors, especially large shipping doors, tightly closed.
3. Increase surveillance of building pipelines, flowlines, and safety-related
equipment during periods of extreme cold. Provide sufficient watch service
to ensure that all plant areas can be visited each hour.
4. Check room temperatures, and use temporary heaters in those areas where
temperatures drop below 40 degrees F.
5. After a prolonged period of abnormally cold weather, make drain tests of
sprinkler risers wherever possible to determine if underground mains are
frozen. Open the drain wide, let it run for 30 seconds or more, then shut
it off. If the pressure fails to return to normal promptly, clear the
mains of ice as soon as possible.
COLD-WEATHER PROGRAMS RELATED TO HAZARDOUS MATERIALS
When cold weather causes pipes and hoses to burst, valves to break, or
containers to crack, potentially hazardous material may be released. In the
winter of 1988, one DOE facility reported that a polyethylene container,
which ruptured after being left outdoors in freezing weather, spilled
approximately 7 liters of extremely hazardous alkaline waste onto a facility
parking lot. Among the incidents reported in December 1990 was the release
of approximately 25 gallons of highly explosive process waste water when a
pipe froze and burst.
During the winter months, cycles of freezing and thawing may also weaken
valves and cause them to rupture. Oil leaks occurred at a number of DOE
facilities because check valves or dump valves failed following cycles of
winter freezing and thawing.
Recommendations
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1. Ensure that all containers used for hazardous or toxic materials are
properly stored, and inspect them for deterioration prior to handling. If
containers become brittle (due to the combination of chemical attack,
freezing temperatures, and ultraviolet light), they may break when moved.
2. Liquids should not be permitted to remain in unheated process lines during
periods when production has been stopped. All lines should be drained and
purged to prevent future line breakage due to freezing temperatures.
3. Ensure that piping and valves (particularly check valves and dump valves)
in systems that carry hazardous or toxic substances are properly insulated.
Install insulators such as heat blankets, heat tape, or frost boxes, as
appropriate.
4. Inspect all anti-freeze loop valves to ensure that they are in the open
position. Chain and lock them in the open position if possible.
COLD WEATHER PROGRAMS FOR BUILDINGS AND EQUIPMENT
Lack of heat frequently causes building and equipment problems in severely
cold weather. However, inadequate communication among personnel, inadequate
procedures, and inadequate design and maintenance directly contribute to cold
weather damage. When a building at one DOE facility was damaged due to a
broken sprinkler system, investigators found that the maintenance staff had
not turned on the HVAC (heating, ventilation, and air conditioning) system
and the operating staff had allowed outside air ducts to remain open.
Although the cold air that entered the building caused sprinkler heads to
break, it was the communication failure between maintenance and operating
staff and their lack of awareness conderning the impact of severely cold air
that led to the damage. In another incident, approximately 19 hours of
reactor operation were lost because a timer failure allowed condensation to
freeze in the instrument air lines, which caused a loss of air to the reactor
building ventilation exhaust valve. A loose solder connection was a
contributing cause of this incident.
Recommendations
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1. Ensure that operations/maintenance personnel communicate relevant cold
weather information regarding the status of equipment, heating,
ventilation, etc. Communicating such information is imperative during
shift turnovers when extremely cold weather is anticipated.
2. Include specific checks for adequate cold weather protection in written
equipment maintenance procedures. Follow any special manufacturer-
recommended procedures related to seasonal changes (e.g., using oil of
different viscosity).
3. Evaluate equipment design problems that are exacerbated by cold weather.
Replace, repair, or re-design equipment and systems as appropriate.
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This publication is one of several bulletins published to share information
with DOE program managers and contractors concerning potential occupational
safety and health problems. For more information or additional copies,
contact Eleanor Crampton, Performance Performance Indicator Division,
Assistant Secretary for Environment, Safety & Health, U.S. Department of
Energy, Washington, DC 20545; telephone FTS 233-3732, Commercial (301)
353-3732.
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